Start stop battery charging message

[Angry Steve]

I apparently must have not done enough starts on the IBS after I replaced it. Yesterday on my way home from work ESS began functioning normally. 3 months several trips to the dealer and a set of batteries and a $60 dollar sensor I’m finally fixed.

Sponsored

 

[Martial Fartist]

Just finding this happening on my 21 jlur. I’m still under warranty. This should be covered correct?

 

[Ang1Sgt]

Okay, new to me 2020 Willys. I’ve seen this charging thing a few times, but when does it actually WORK on a Manual equipt Jeep? I think I have triggered it once or twice, but it does not work like that of my Subaru Outback. Thank God I have a button on the center screen to turn the auto start off. The battery in the Subi does not have the CCA that it should with this system.

 

[SparkleTooth]

So I am now a bit confused on this. I am actually going to be replacing both my batteries this week. I too am getting the ESS battery charging message, so I figured now would be a good time to replace both.

I never considered the IBS scenario. Is this something I will actually need to do when replacing both batteries? Somehow this doesn't make a lot of sense to me. Thoughts?

 

[Rhinebeck01]

So I am now a bit confused on this. I am actually going to be replacing both my batteries this week. I too am getting the ESS battery charging message, so I figured now would be a good time to replace both.

I never considered the IBS scenario. Is this something I will actually need to do when replacing both batteries? Somehow this doesn't make a lot of sense to me. Thoughts?

@SparkleTooth

Just unplug the IBS sensor(easy, takes 2 sec) and then go about / do your change out of the 2 batteries.

Be sure the 2 batteries you are installing are fully charged.

After the install of the 2 batteries, plug the IBS sensor back in.

Now, the IBS starts a lengthy relearn process.

Until the relearn process is complete, accurate battery state (MAIN battery) information is unavailable to other vehicle systems. EVIC messages, this will be a tad flakey until relearn..

This relearning process requires 5 normal, operator initiated starts with at least eight hours off time between each start. Usually, the process takes a few days of vehicle operation to complete.


.

 

[SparkleTooth]

Just an update: Even though I am still under warranty, there is no way I am wasting my time at the dealer. So I ordered a DieHard AGM Main Battery and a Diehard Aux battery. When I pulled the old batteries out I tested them and both were around 12.4v.

I tested both the new batteries and both were in the 12.7v range. I disconnected the IBS while i was removing everything and installed the new batteries and reseated the IBS.
Well I still get the same Start/Stop battery charging message, but I am just going to assume 1 of 2 things.
1. The IBS has to relearn and go through 5 cycles with 8 hours in between (or whatever the cycle times are)
OR
2. Start/Stop is just another feature to complex for FCA to handle.

I always disable start/stop anyway so I don't care if it never works, I just don't want it to develop into some other issue down the road.

 

[mwilk012]

So I am now a bit confused on this. I am actually going to be replacing both my batteries this week. I too am getting the ESS battery charging message, so I figured now would be a good time to replace both.

I never considered the IBS scenario. Is this something I will actually need to do when replacing both batteries? Somehow this doesn't make a lot of sense to me. Thoughts?

no. Remove both batteries, then replace both batteries.

 

[SparkleTooth]

no. Remove both batteries, then replace both batteries.

Huh?......anyway I removed both old batteries and replaced with two new batteries.

 

[jeepoch]

Just finding this happening on my 21 jlur. I’m still under warranty. This should be covered correct?

Christopher,

Asking the dealership to fix this is like farting in the wind...

I was foolish enough to think they had the expertise to diagnose this. My dealership did not. Nor do I suspect any of them do. I got nothing but a run around and a plethora of excuses.

Because my 2019 was under warranty at the time, still under 30K miles, I had told myself let's play this silly game until they delivered a good solution. Hopefully a quick one.

Unfortunately not. After over a half dozen trips to their service dept, the following things occurred:

• They kept the Jeep on a charger nearly all day twice. Even though I told them I leave it on a 15A / 3A trickle charger every night. They continued to state no issue found.

• After this, they finally started replacing the IBS sensor. Twice. The second time they told me that the first one replaced must have been defective. Either they did nothing but give me lip service the first time around, or they were just guessing and replaced the cheapest and easiest thing first, (twice). Also for the record, I'm no slouch when it comes to technology, I understand the 're-learning' cycles needed to measure the charge / discharge dynamics on dissimilar sized batteries connected in parallel. I was however very patient in continuing to put up with the constant ESS complaints "Battery Charging" and "Battery Protection Mode" indications.

• Each and every time I had come in, they had run load tests on both batteries independently, or so they claimed. My suspicion is they load tested the system without disconnecting anything.

• Only after they realized that I wasn't going away did they start getting serious. They then begrudgingly replaced the AUX battery only. They were quite stubborn and insistent that the MAIN was OK.

• The ESS only just started to work after this, but still just sporadically. I was still patient but as usual, the Battery Voltage continued to display nothing lower than 14.5v. Sometimes even as high as 14.7v. This is just nuts.

• After another couple of conversations and battery charging episodes later, they were still unwilling to replace the MAIN, unless I was willing to shell out $220 to have them replace it out of pocket on my own dime.

• Argh... I finally convinced myself that this was nothing but futile dealing with these schmucks. I went and purchased a good AGM battery for less than half of what they quoted, replaced it myself and have never looked back.

My Battery Voltage now constantly reads in the high 12 to low 13v all the time. ESS is always available. It comes on the dozens of times I'm stopped at traffic lights on my normal daily commute. And I have not yet needed an overnight trickle charge as I had been doing for the past several months.

Granted, I had never (ever) been stranded, the Jeep started up always flawlessly within the first few revolutions of crankshaft rotation. I suppose this was the only reason why I was so damn patient and stupid. I had really given my dealership every opportunity to make this work. I'll never be that stupid again.

CONCLUSION:
When ESS starts complaining about batteries, believe it. Troubleshoot it to you're blue. My knee-jerk reaction will be to replace both batteries and then troubleshoot after that doesn't work.

Charging two dissimilar sized batteries in parallel from a single alternator is insanely ludicrous. No automotive engineer worth their salt would have ever designed this intentionally. It certainly seems to me that this ESS system was pushed through within some very tight schedule likely to satisfy some hard EPA or CAFE mandates.

It just amazes me how much the dealership absolutely refused to even consider true root cause. The corporate pain of this awful design must be severe. To put customers through this wringer just to not spend the cost of new batteries.

I weep for the EV debacle about to be forced down our throats. God save us.

Jay

 

[SparkleTooth]

Here is some very informative information about the Battery / Charging system that may help answer/diagnose some of your issues.


SYSTEM OPERATION - DUAL BATTERY 12 VOLT BATTERY SYSTEM
The dual battery Engine Stop/Start (ESS) system consists of four main components that are connected to and operate the starting, charging and vehicle electrical systems. These are the main battery, auxiliary battery, Power Control Relay (PCR) and dual battery system fuse. The power control relay separates the system into two sides, the main battery side and auxiliary battery side. The generic graphic below shows a simplified diagram of the components for ease in understanding the system configuration.

• The main battery is the larger battery that is directly connected to the starter and alternator when the batteries are isolated.
• The auxiliary battery is the smaller battery that is directly connected to the Power Distribution Center (PDC) powering the modules and accessories when the batteries are isolated. The negative cable for the auxiliary battery connects to the main battery negative cable end.

There is an Intelligent Battery Sensor (IBS) connected in series on the main battery negative cable which provides information about the batteries to the Body Control Module (BCM) over a Local Interface Network (LIN) bus. The IBS monitors the current flow going out of the battery, and current flowing into the battery during charging to make these calculations. Some of the information stored and provided by the IBS are:

• Battery voltage
• Battery temperature
• Battery State of Charge (SOC) - The battery SOC is the percentage of battery charge based on measured voltage, charge and discharge rates.
• Battery State of Function (SOF) -The SOF is the calculated voltage that the battery will drop to when the starter is engaged to crank the engine.
• Battery State of Health (SOH) - The SOH is the measurement of current battery capacity along with depreciation in battery health.

The BCM broadcasts the IBS data over the CAN bus. The Powertrain Control Module will use the battery SOC to determine charge rates as well as when to allow features such as the Engine Stop/Start (ESS) system to function. The BCM will uses the battery information received from the IBS to make decisions on load shedding when battery SOC is determined to be low.

In a normally functioning system, the two batteries and sides of the system are always connected through the power control relay except for the brief periods during cranking events. Both batteries are connected to the entire electrical system during this mode. This allows charging of the auxiliary battery through it’s connection to the main battery side, and the main battery to be connected to the Power Distribution Center (PDC) and assist the auxiliary battery in operating the modules and accessories. Since the batteries are nearly always connected, the IBS info provided will be the average SOC of the two batteries. The PCM can determine the SOC of each battery during a cranking event when the batteries are isolated for a brief period during initial starter engagement. During this period, the battery voltage provided to the PCM is coming from only the auxiliary battery, and the battery voltage reported from the IBS will only be reporting the main battery voltage. This helps the PCM to make a determination on allowing ESS operation.

FUNCTIONAL DESCRIPTION - BATTERIES
Batteries are designed to store electrical energy in a chemical form. A standard 12 volt battery will typically have 6 cells connected in series that are made up of a positive and negative plate. Each cell will typically provide approximately 2.1 volts. As the battery discharges, the flow of electrons causes a chemical reaction between the sulfuric acid and the plates causing the plates to become sulfated with lead. Charging the battery will reverse the process, changing the plates back into spongy lead and lead dioxide, and the water back into sulfuric acid.

The battery is vented to release excess hydrogen gas that is created when the battery is being charged or discharged. However, even with these vents, hydrogen gas can collect in or around the battery. If hydrogen gas is exposed to flame or sparks, it may ignite. If the electrolyte level is low, the battery may arc internally and explode.

The dual battery Engine Stop/Start (ESS) system has a main battery and auxiliary battery.

• The main battery is the larger battery that is directly connected to the starter and alternator when the batteries are disconnected.
• The auxiliary battery is the smaller battery that is directly connected to the Power Distribution Center (PDC) powering the modules and accessories when the batteries are disconnected.

In a normally functioning system, the two batteries and sides of the system are always connected through the power control relay except for the brief periods during cranking events. Both batteries are connected to the entire electrical system during this mode. This allows charging of the auxiliary battery through it’s connection to the main battery side, and the main battery to be connected to the Power Distribution Center (PDC) and assist the auxiliary battery in operating the modules and accessories.

CHARGING AND TESTING THE BATTERIES: The batteries should be charged one of two ways depending on the situation and reason for charging.

1. CHARGING USING THE GR8 BATTERY TESTER - It was previously documented to never blind charge a vehicle at the pole clamp. However, if the vehicle is brought in with a battery issue or complaint, and the battery is being charged and tested using the GR8 Battery Tester, the tester should be connected directly to the Pole clamp at the negative Battery post. With the updates done on the GR8 Battery Tester, it will not test the battery correctly if connected and charged through the IBS. After performing any testing requiring blind charging, a battery has been replaced or after any repairs are made, the IBS learning curve should be initiated to allow the IBS to update quickly. See the IBS Component Functional Description section for details on initiating the IBS learning curve.
2. CHARGING USING A STANDARD BATTERY CHARGER - This should only be performed if the vehicle was not brought in for a battery issue and the batteries are depleted during service. the batteries should be charged through the IBS. To do this the negative clamp on the charger should be placed on the negative cable attachment to the IBS, the Jump Post terminal if equipped, or a good chassis ground, NOT the Pole clamp at the negative Battery post. Without proper clamp placement, the IBS data will not update.

The PCM performs diagnostics to determine if the batteries are connected and disconnected at the appropriate times. To do this the PCM monitors the main battery voltage from the IBS feedback and the auxiliary battery voltage from the fused B+ circuit at the PCM.

FUNCTIONAL DESCRIPTION - BATTERY CABLES
The battery cables connect the battery terminal posts to the vehicle electrical systems. These cables also provide a path back to the battery for electrical current generated by the charging system to restore the voltage potential of the batteries. The female battery terminal clamps on the ends of the battery cables provide a strong and reliable connection of the battery cable to the battery terminal posts. The terminal pinch bolts allow the female terminal clamps to be tightened around the male terminal posts on the top of the battery. The eyelet terminals secured to the opposite ends of the battery cables from the female battery terminal clamps provide secure and reliable connection of the battery cables to the vehicle electrical systems.

On dual battery systems, the negative battery cable from the auxiliary battery connects to the negative battery cable of the main battery at the battery cable end. Both batteries are then grounded through the main battery cable connection to ground.

FUNCTIONAL DESCRIPTION - BODY CONTROL MODULE (BCM)
The Body Control Module (BCM) is the gateway for all bus communications needing to be gated from one bus network to a different bus network.

The BCM obtains battery voltage information from the Intelligent Battery Sensor (IBS) over the Local Interface Network (LIN) bus. The BCM is the LIN master for the IBS and manages the IBS initialization, LIN communication, signal gating and IBS diagnostics.

Load Shedding

Using the LIN, the BCM communicates with the IBS to provide load shedding. Load shedding is activated under the following conditions:

• The engine must be running with an engine speed equal to or higher than 400 RPM for greater than 50 seconds.
• The battery State of Charge (SOC) supplied signal value sent by the IBS over the LIN bus to the BCM must be less than or equal to 55%.
• The battery voltage measured by the IBS and supplied to the BCM over the LIN bus must be less than or equal to 12.2 volts.

When the vehicle is in a load shed operating state, the BCM will bus a signal to the Instrument Panel Cluster (IPC) to illuminate the "Battery Saver On" indicator.

If the battery SOC rises to a level equal to or greater than 65% and the battery voltage rises to 13 volts or higher, load shedding will begin to reverse itself putting the vehicle back to a normal operating state.

Any transition of the ignition state will reset all of the load shed output signals and therefore cancel load shedding operation.

Battery Critical State

If the battery SOC is equal to or less than 35% and the battery voltage is equal to or less than 11.8 volts, a "Battery Reached Critical State" output signal is broadcast by the BCM. Another condition to set this output signal is that the battery voltage is less than or equal to 10.9 volts and the state of charge is less than or equal to 55%.

When the battery reaches critical state, only electrical loads essential to vehicle operation are allowed to be turned on. The following actions are recommended to be taken:

• Heated seats and the heated steering wheel are disabled for the duration of the ignition cycle
• Rear defroster and heated mirrors time out in 30 seconds each time the customer turns them on for the duration of the ignition cycle
• The Heating, Ventilation, and Air Conditioning (HVAC) system is allowed only minimal loads for visibility requirements for the duration of the ignition cycle
• On vehicles equipped with an eTorque system, the Power Inverter Module (PIM) is disabled for the duration of the ignition cycle
• Audio and Telematic systems will only allow minimal loads for communications and emergency requirements for the duration of the ignition cycle

There is no load shed recovery for a battery critical state and the vehicle operation will remain in this state until the ignition is cycled.

Inputs

• Battery voltage, temperature and state of charge information is provided through LIN communication from the IBS

Outputs

• IBS LIN communication for strategy management
• The BCM broadcasts the battery information on both the Controller Area Network-Chassis (CAN-C) and the CAN-Interior High Speed (CAN-IHS) data bus networks
• Load shedding management to the relevant nodes on all bus networks

FUNCTIONAL DESCRIPTION - INTELLIGENT BATTERY SENSOR (IBS)
The Intelligent Battery Sensor (IBS) is an electrical shunt with a microprocessor that is mounted in-line with the negative battery cable. The IBS monitors the battery voltage as well as current flow into and out of the battery. The IBS has a built-in thermistor that calculates the battery temperature. The microprocessor uses this data to calculate battery State of Charge (SOC), battery internal resistance, charge received, electrical demand, and time in service. This information is reported through the LIN Bus circuit to the Body Control Module (BCM). The BCM broadcasts the information to the Powertrain Control Module (PCM) over the CAN Bus.

The IBS SOC data is also used by the BCM and other modules to determine when to begin disabling certain vehicle features that draw excessive electrical loads due to a low battery SOC. The SOC threshold for starting to disable features can vary based on vehicle and engine but is typically in the 50% to 60% range.

On the dual battery Stop/Start systems, the IBS is connected to the main battery. Since the two batteries are connected to each other most of the time, the battery SOC reported by the IBS is reporting the average SOC of the two batteries. It is possible for one battery to be fully charged and the other battery discharged causing the overall SOC to be low. If the SOC is low, both batteries should be checked for proper charge and functionality before checking for an issue with the IBS.

The IBS SOC may read low when both batteries test good. The following items can contribute to, and should be considered when diagnosing a low SOC condition before replacing an IBS or battery:

• If the vehicle is jump started at the battery posts bypassing the IBS.
• If the battery is blind charged at the battery posts bypassing the IBS.
• Repeated short trip driving events not allowing enough charge time.
• The IBS accuracy is off and needs to relearn the battery SOC.

Depending on the vehicle, there could be a non-MIL DTC (P057F) set, or an EVIC message indicating a low battery state of charge limiting some features, such as ESS. In some cases, properly charging the batteries through the IBS can raise the IBS SOC enough to regain functionality and repair the issue. However, it can sometimes take two or three, 4-hour BUS off sleep cycles for an IBS to learn and update the battery SOC. The IBS can be initiated into a learning curve by completely disconnecting the IBS from the battery, and disconnecting harness connector for 20 seconds. The IBS battery feed, LIN Bus and ground circuits should be checked before reconnecting the IBS. The IBS should default to approximately 80% SOC when reconnected. However, the IBS accuracy is determined to be low until the IBS can relearn battery SOC. This occurs after an engine run cycle and a subsequent ignition off sleep cycle of between one to four hours. Some features will be disabled until the IBS SOC is updated.

FUNCTIONAL DESCRIPTION - POWER DISTRIBUTION CENTER (PDC)
The Power Distribution Center (PDC) is designed to provide safe, reliable, centralized and convenient access to distribution of the electrical current required to operate all of the many standard and optional factory-installed electrical and electronic powertrain, chassis, safety, comfort and convenience systems. At the same time, these systems were designed to provide centralized locations for conducting diagnosis of faulty circuits and for sourcing the additional current requirements of many aftermarket vehicle accessory and convenience items. The PDC connects directly to the Battery Positive (B+) cable.

The power distribution systems also incorporate the following various types of circuit control, and protection features:

• Automatic resetting circuit breakers
• Cartridge fuses
• Blade fuses
• Removable relays
• Non serviceable Printed Circuit Board (PCB) relays

 

[SouthernJL]

Christopher,

Asking the dealership to fix this is like farting in the wind...

I was foolish enough to think they had the expertise to diagnose this. My dealership did not. Nor do I suspect any of them do. I got nothing but a run around and a plethora of excuses.

Because my 2019 was under warranty at the time, still under 30K miles, I had told myself let's play this silly game until they delivered a good solution. Hopefully a quick one.

Unfortunately not. After over a half dozen trips to their service dept, the following things occurred:

• They kept the Jeep on a charger nearly all day twice. Even though I told them I leave it on a 15A / 3A trickle charger every night. They continued to state no issue found.

• After this, they finally started replacing the IBS sensor. Twice. The second time they told me that the first one replaced must have been defective. Either they did nothing but give me lip service the first time around, or they were just guessing and replaced the cheapest and easiest thing first, (twice). Also for the record, I'm no slouch when it comes to technology, I understand the 're-learning' cycles needed to measure the charge / discharge dynamics on dissimilar sized batteries connected in parallel. I was however very patient in continuing to put up with the constant ESS complaints "Battery Charging" and "Battery Protection Mode" indications.

• Each and every time I had come in, they had run load tests on both batteries independently, or so they claimed. My suspicion is they load tested the system without disconnecting anything.

• Only after they realized that I wasn't going away did they start getting serious. They then begrudgingly replaced the AUX battery only. They were quite stubborn and insistent that the MAIN was OK.

• The ESS only just started to work after this, but still just sporadically. I was still patient but as usual, the Battery Voltage continued to display nothing lower than 14.5v. Sometimes even as high as 14.7v. This is just nuts.

• After another couple of conversations and battery charging episodes later, they were still unwilling to replace the MAIN, unless I was willing to shell out $220 to have them replace it out of pocket on my own dime.

• Argh... I finally convinced myself that this was nothing but futile dealing with these schmucks. I went and purchased a good AGM battery for less than half of what they quoted, replaced it myself and have never looked back.

My Battery Voltage now constantly reads in the high 12 to low 13v all the time. ESS is always available. It comes on the dozens of times I'm stopped at traffic lights on my normal daily commute. And I have not yet needed an overnight trickle charge as I had been doing for the past several months.

Granted, I had never (ever) been stranded, the Jeep started up always flawlessly within the first few revolutions of crankshaft rotation. I suppose this was the only reason why I was so damn patient and stupid. I had really given my dealership every opportunity to make this work. I'll never be that stupid again.

CONCLUSION:
When ESS starts complaining about batteries, believe it. Troubleshoot it to you're blue. My knee-jerk reaction will be to replace both batteries and then troubleshoot after that doesn't work.

Charging two dissimilar sized batteries in parallel from a single alternator is insanely ludicrous. No automotive engineer worth their salt would have ever designed this intentionally. It certainly seems to me that this ESS system was pushed through within some very tight schedule likely to satisfy some hard EPA or CAFE mandates.

It just amazes me how much the dealership absolutely refused to even consider true root cause. The corporate pain of this awful design must be severe. To put customers through this wringer just to not spend the cost of new batteries.

I weep for the EV debacle about to be forced down our throats. God save us.

Jay

Man... This is a LOT. I still intend to take mine to the dealership. Hopefully my experience will be different from yours. I actually may email your entire comment to them to give them a head start on how to properly troubleshoot the issue.

 

[mwilk012]

Man... This is a LOT. I still intend to take mine to the dealership. Hopefully my experience will be different from yours. I actually may email your entire comment to them to give them a head start on how to properly troubleshoot the issue.

Is yours under warranty? It's very simple to replace the batteries. The dealership will only replace with more low quality mopar batteries.

 

[Yawnie'sPapa]

Just a few things to keep in mind when you have this message, but the most important to begin with when ESS doesn't work it can be a sign of the following:

1. Batteries can be dead.
2. Alternator can be shot
3. IBS can be defective

Quick way to troubleshoot:

1. If the battery voltage on the dash is constantly above 14+ it means for some reason the IBS is constantly trying to charge your battery, that is a bad sign. Modern battery systems in conjunction with IBS don't do this anymore, so this is the first indicator that something can be wrong with the battery. So time to check main battery and the auxiliary one, remember torque doesn't have the auxiliary battery.
2. Check the voltage of the new battery, ideally it should be around 12.7. If not charge it up to that.
3. If message is still showing, reset the IBS that is located by the black battery terminal, unplug the cable and wait about 10 minutes for it to be fully reset.
4. Message still showing ? At this point it could be either the IBS that is shot or the alternator.
5. Test the alternator, if it's fine replace the IBS sensor.

Just went through this a few days ago. I had the same message for about 2 years. In my case replacing the battery alone fixed the problem. But I had to wen all the way through and replace the IBS on a friend Wrangler.

Sorry, wrong on several counts.
On #1 about voltage - nope. If it's cold out, it will charge above 14v almost all the time unless you drive it daily and you drive it for an hour each day.
Mine is fine, new, in fact, and when the temperatures are below 40, since I drive it only every 2 or 3 days, the voltage has been around 15.0 most of the time. It's finally in the low 14s with warmer weather and I've seen 13s since driving it a bit more in the past few days.
That's a change from earlier model years.

Incorrect on the alternator, too (my history is as an auto electrician, and restorer of charging systems) - if the alternator was shot, your running voltage would be under 13 all the time and you'd be seeing 12.x volts after a few minutes of running as the Jeep's systems drained the batteries.
That message isn't normally the IBS - in fact, in almost every case I've worked on, the IBS only needed to be reset - and removing it from the battery and unplugging it is a sure way to reset it.
Telling someone to replace the IBS because they still have the battery charging issue after resetting it - not right.

There's so much incorrect with that post I could go on for paragraphs.

 

[SouthernJL]

Is yours under warranty? It's very simple to replace the batteries. The dealership will only replace with more low quality mopar batteries.

Yes mine is still under warranty. This is why I want to have Jeep cover the costs instead of me doing so. Even if they replace with more lower quality batteries, if they last another 2 years, that will take me till I'm out of warranty and they I'll purchase better batteries at that future date.

 

[SparkleTooth]

Here are the scenarios for Temp and ESS

EVIC Warning Messages for ESS
ESS EVIC Message	ESS EVIC Message Reason/Repair Action
Stop/Start Not Available	During ECM wake-up and Stop/Start not ready at key On indicating engine off.
Stop/Start Active	Indicates engine is off during an Autostop.
Stop/Start Not Ready Driver Seatbelt Unbuckled	Driver’s seatbelt is unbuckled prior to an Autostop.
Stop/Start Not Available Driver Not Detected	Driver Presence Detection Module indicates driver’s seat is unoccupied for applications with removable doors only.
Stop/Start Not Ready Driver Door Open	Driver’s door is open, prior or during an Autostop.
Stop/Start Press Clutch or Shift To Neutral	Shifting into gear during an Autostop without pressing the clutch. (For MTX vehicles only).
Stop/Start Restart Required Fault Detected	During an Autostop/Autostart, the ECM/PCM detects a DTC calibrated to be an Engine Start inhibit trigger. Repair DTCs and retest.
Stop/Start Not Available Service Battery Radio display and functions may be inoperative to the customer.	In order to allow the ESS Autostop, the Battery State of Charge (SOC) must be greater than the threshold reported in the table as following: IBS SOC Temperature Minimum SOC to allow ESS Autostop (-20°C) -4°F 100 (-16°C) 3.2°F 100 (-15°C) 5°F 80 (-1°C) 30.2°F 80 (0°C) 32°F 70 (15°C) 59°F 70 (35°C) 95°F 70 (50°C) 122°F 70 (59°C) 138.2°F 70 (60°C) 140°F 100 (80°C) 176°F 100 Main 12 Volt Battery does not successfully pass a load test or Battery is sulfated. Auxiliary Battery does not successfully pass a load test or Battery is sulfated.
Stop/Start Not Ready Battery Charging Radio display and functions may be inoperative to the customer.	In order to allow the ESS Autostop, the Battery State of Charge (SOC) must be greater than the threshold reported in the table as following: IBS SOC Temperature Minimum SOC to allow ESS Autostop (-20°C) -4°F 100 (-16°C) 3.2°F 100 (-15°C) 5°F 80 (-1°C) 30.2°F 80 (0°C) 32°F 70 (15°C) 59°F 70 (35°C) 95°F 70 (50°C) 122°F 70 (59°C) 138.2°F 70 (60°C) 140°F 100 (80°C) 176°F 100 Main 12 Volt Battery does not successfully pass a load test or Battery is sulfated. Auxiliary Battery (if Equipped) does not successfully pass a load test or Battery is sulfated.
Stop/Start Fail	During engine running, ECM/PCM detects a DTC calibrated to be an Engine Off inhibit trigger. Repair DTCs and retest.
Stop/Start Not Available	Message Indicates “not ready” during engine running and any of the Engine Off AND Engine Start conditions are FALSE.
Stop/Start Ready	ATX: while vehicle is moving and during engine running, ESS ready to allow an Autostop (all Engine Off AND Engine Start conditions are true) ESS will enter an Autostop once TransReadyForESS = True, Master Cylinder input threshold, and Vehicle speed is below threshold. MTX: While vehicle is moving and engine running, ESS ready to allow an Autostop (all Engine Off AND Engine Start conditions are true) once Vehicle speed is below threshold, Gear is in Neutral and Clutch pedal is released.
Stop/Start Off	Indicates ESS disable switch pressed, ESS is inhibited. No Autostop while engine running. Autostart if ESS disable switch pressed during Autostop. ESS disable switch status resets with every key cycle.
Stop/Start Not Ready Hood Open	Indicates hood is open. Inhibits Autostops while engine running.
Stop/Start Not Ready Accelerator Depressed	Vehicle speed below Autostopping threshold, brake pedal is pressed AND accelerator pedal is pressed. Inhibits Autostops while engine running. Initiates an Autostart during an Autostop.
Stop/Start Not Ready Battery Protection Mode Radio display and functions may be inoperative to the customer.	With the scan tool, verify that the Battery State Of Function (SOF) status is not “False.” In order to allow the ESS Autostop, the Battery State of Function from the Intelligent Battery Sensor (IBS) must be greater than the threshold reported in the table below: IBS SOF Temperature Minimum SOF to allow the ESS Autostop (-15°C) 5 °F 7 (-5°C) 23°F 7 (5°C) 41°F 7 (15°C) 59°F 7 (25°C) 77°F 7 (35°C) 95°F 7 (45°C) 113°F 7 (60°C) 140°F 7
Stop/Start Not Ready Tow Active	When Tow/Haul mode is active, ESS is inhibited. Autostart is triggered if Tow/Haul Switch (if Equipped) is pressed during an Autostop.
Stop/Start Not Ready 4Low Active	T-Case is in 4Wheel Low mode. Present on vehicles with T- Case (4Wheel Low).
Stop/Start Not Ready Too Steep	Indicates grade above calibrated threshold to allow Autostop. Triggers an Autostart during an Autostop if grade threshold is above +7% or below -10%.
Stop/Start Not Ready Cabin Cooling or Heating	Indicates HVAC demand via the CAN C Bus.
Stop/Start Not Ready Max Cooling or Heating	When HVAC max button is pressed by customer. Indicates HVAC demand via CAN C signal. Inhibits Autostops while pressed. Triggers an Autostart if pressed during an Autostop.
Stop/Start Not Ready Front Defrost Selected	Indicates Front Defrost active. Triggers an Autostart during an Autostop and inhibits Autostops if active during engine running.
Stop/Start Not Ready Turned Steering Wheel	Indicates steering wheel is being turned. Inhibits Autostops if present during engine running. Triggers Autostarts if active during and Autostop.
Stop/Start Not Ready Engine Temp Too Low	Indicates either coolant, or oil, or catalyst engine temperature is lower than calibrated threshold. Inhibits Autostops during engine running and triggers an Autostart during an Autostop event. For engine coolant temperature, see table below: Minimum Engine Coolant Temperature To Allow Autostop Event Ambient Temperature (80°C) 176 °F (-16°C) 3.2 °F (70°C) 158°F (0°C) 32°F (60°C) 140°F (10°C) 50°F (55°C) 131°F (15°C) 59°F (45°C) 39.2°F (20°C) 68°F (40°C) 104°F (25°C) 77°F (40°C) 104°F (30°C) 86°F (40°C) 104°F (35°C) 95°F (40°C) 104°F (40°C) 104°F Minimum Engine Oil Temperature To Allow Autostop Event Ambient Temperature (50°C) 122 °F (0°C) 32°F (40°C) 104°F (5°C) 41°F (35°C) 95°F (10°C) 50°F (30°C) 86°F (15°C) 59°F (25°C) 77°F (20°C) 68°F (25°C) 77°F (25°C) 77°F (25°C) 77°F (30°C) 86°F (25°C) 77°F (35°C) 95°F (25°C) 77°F (40°C) 104°F Minimum Catalyst Temperature to allow an ESS AutoStop event is (440°C) 824°F.
Stop/Start Not Ready DEF RGN (if Equipped)	During engine running, ECM inhibits Autostops when Regen is active.
Stop/Start Not Ready Service Battery Vehicle Shut Off	During a failure of the Power Control Relay (PCR). After an Autostop: If Power Control Relay between Cranking Battery and Auxiliary Battery is stuck open, vehicle shuts off within minutes.

The engine will NOT Autostop unless ALL conditions below are TRUE.

If ANY of the conditions below are NOT TRUE Autostop is INHIBITED .

ESS Allow Conditions for Autostop
Condition	Operating Range
Outside Ambient temperature	Greater than 10°F (–12°C) or less than 110°F (43°C)
Driver seatbelt	Buckled
Driver door	Closed
Driver seat pad Driver Presence Detection Module (if equipped)	Occupied – when equipped (on vehicles with removable doors)
Hood	Fully closed (2 Hood Ajar Switch Inputs)
Accelerator pedal	Released
Grade –too steep of an incline/decline	Lesser than +7% OR greater than -10%
Engine operating temperature	Minimum acceptable range: Coolant temperature greater than a calibrated threshold (Function of ambient temp) Engine Oil temperature is greater than a calibrated threshold (Function of ambient temp) Catalyst temperature is greater than a calibrated threshold (Function of ambient temp) Maximum acceptable range: Coolant temperature below a calibrated threshold 239°F (115°C) Engine Oil temperature below a calibrated threshold 239°F (115°C) Catalyst temperature below a calibrated threshold 1742°F (950°C)
Transfer Case Selection	4WD LO = Off Neutral = Off
Manual Paddle shifter	Not selected/active/pressed
Shifter position	Drive (NAFTA ATX) Neutral (NAFTA MTX)
Brake Master Cylinder pressure	Above a calibrated threshold (ATX only)
Hill start assist	Hill start assist brake pressure above calibrated threshold
ESS related OBD faults	No Active OBD DTCs
Brake Booster Vacuum	29.9 kPa (4.34 PSI)
Steering Angle	Below 135 degrees
Tow Haul Mode	Off
ESS Disable Button	Not pressed
PPPA (Parallel Perpendicular Park Assist)	Not active
Altitude	Barometric pressure above: 72 KPa (less than 9,000 ft.)
Brake Pedal	Pressed (while maintaining steady Brake Pedal pressure applied by driver)
ABS Module	Anti-lock brake system is not active
Engine Speed	1100 RPM
ACC+	Stop/Start allowed
Engine run time	2 seconds
Vehicle speed	0 MPH\0 kph (ATX)
Threshold vehicle speed exceeded since last engine Autostart	5 MPH
12 volt Battery Parameters	Voltage more than 11.5 volts SOC above 65% Temperature below 140°F (60°C)

It may be possible for the vehicle to be driven several times without the Stop/Start system going into a Stop/Start ready state under more extreme conditions of the items listed above.

When it comes to Stop/Start, the PCM allows the engine Autostart during an Autostop event when any of the below conditions are TRUE.

ESS Allow Conditions for Autostart
Condition	Operating Range
Ambient temperature	Less than 10°F (–12°C) or greater than 110°F (43°C)
Shifter Position	For NAFTA : Out of Drive or M-Gate For EMEA : Neutral / Reverse
Accelerator Pedal	Pressed
HVAC mode:	HVAC set to AUTO mode Customer changes blower motor speed Rear defrost = No impact to ESS Front Defrost = ON Cabin Hi= ON Cabin Lo= ON Max A/C=ON
HVAC blower speed	Max blower speed selected or blower speed incremented
Grade–too steep of an incline/decline	Greater than +7% OR lesser than -10%
Engine operating temperature	Minimum acceptable range: Coolant temperature less than a calibrated threshold (Function of ambient temp) Engine Oil temperature is less than a calibrated threshold (Function of ambient temp) Catalyst temperature is less than a calibrated threshold (Function of ambient temp) Maximum acceptable range: Coolant temperature above a calibrated threshold 239°F (115°C) Engine Oil temperature above a calibrated threshold 239°F (115°C) Catalyst temperature above a calibrated threshold 1742°F (950°C)
Stop/Start Autostop time active	Exceeded 5 minute timeout
Transfer Case Selection	4WD LO = ON Neutral = ON
Manual Paddle shifter	Active/Pressed during Autostop
Shifter position	Autostart when shifter moved out of Drive
Brake Master Cylinder pressure	Below a calibrated threshold (Below 3bar) Or below a calibrated pressure gradient threshold (ATX only)
Hill Start Assist	Hill Start Assist brake pressure below calibrated threshold
ESS related OBD Faults	Calibrated active to allow Autostart Example: U0131–00 active DTC
Brake Booster Vacuum	29.9 kPa (4.34 PSI)
Steering Angle	Above 135 degrees
Tow Haul Mode	On
ESS Disable Button	Pressed
PPPA (Parallel Perpendicular Park Assist)	Activated
Brake Pedal	Released
ACC+	Cancelled/disengaged
Vehicle speed	Above 0 MPH/0 kph (ATX) Above 1.5 MPH/3 kph (MTX)
12V Battery Parameters	Voltage Less than 11.5 V (trigger Autostart when below 11.5 V) SOC Below 65% Temperature Above 140°F (60°C) Main 12 Volt Battery does not successfully pass a load test or Battery is sulfated. Auxiliary Battery does not successfully pass a load test or Battery is sulfated.

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