How to measure the parasitic battery drain

TroyBoy

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Warning! DO NOT disconnect the negative battery cable from the ground and then place the multi-meter in between. This initial hit spikes over 10A and will blow the multi-meter fuse. I tried that 4 times before I figured out a better way. The damn fuse is not easy to replace in those meters!

1) Remove this nut but leave the wire on. This is the ground for both batteries.
Step1.JPG


Set up the Multi-meter:
1) Set to Amps DC. Mine is automatic. If yours is not automatic then start with something larger first like 100A and then work your way down.
2) Make sure it says it is for DC not AC
3) Switch the red wire from 'INPUT' to '10A'
Step2.JPG


Connect the multi meter leads:
It is important that you do this while the negative battery wire is still connected to the ground! This is because the first connection of the negative battery wire to the ground spikes the current draw over 10 amps and blows your multi-meter fuse. I don't know why this is but I blew 4 fuses in my multi-meter before I came up with this way to get around the initial spike.
1) Connect the red multi-meter lead to the negative cable
2) Connect the black multi-meter lead(now a green alligator clip)
3) Push the negative cable off the bolt to begin the readings on the multi-meter

By doing it this way the negative cable always remains connected to the ground in on form or another.
Step3.JPG


My parasitic draw was 134 mA: (ignore the negative, I had the leads reversed the first time)
10minutes.JPG


Playing around, I disconnected the multi-meter, disconnected the negative cable to the ground which cut the power to the Jeep. I then put the negative cable back on making sure it grounded but no nut. I quickly reattached the multi-meter and then pushed the negative cable back off the bolt.

This resulted in a 4.9 Amp reading initially and quickly dropped down to around 2.5 Amps. After about 30 seconds the current dropped down to 1.5 Amps and stayed there for 5.5 minutes. It then dropped to 230 mA. After around 20 minutes I get around 140 mA.





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CanAmMick

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Any type of programmer on your Jeep?
 
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Any type of programmer on your Jeep?
I just read your post on the other thread and was going to respond. I did have battery issues. I've had the Tazer since it first came out with 11.0.3. One day I decided to try the ESS and it wouldn't work anymore. The batteries looked fine and started the jeep just fine but ESS wouldn't work. Page 6 of the EVIC showed either ESS Charging or ESS not ready but I can't remember. At this point I've had the jeep for 10 months and took it to the dealer to have it fixed. They did a test on the batteries and found both to be bad so they replaced both batteries with new ones. About a month later I upgraded to 11.0.7 and two days later my batteries are completely dead. I immediately unmarried the tazer and removed it. I used a smart charger to charge the battery back up overnight. A week of ESS working perfectly, I decided to reinstall the tazer just for the Cargo Cam, Tire Size and TPMS using 11.0.6. I then removed the tazer but kept it married. I've been driving like this for a few weeks now but it did make me wonder what the actual parasitic draw was on these jeeps.
 

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I just read your post on the other thread and was going to respond. I did have battery issues. I've had the Tazer since it first came out with 11.0.3. One day I decided to try the ESS and it wouldn't work anymore. The batteries looked fine and started the jeep just fine but ESS wouldn't work. Page 6 of the EVIC showed either ESS Charging or ESS not ready but I can't remember. At this point I've had the jeep for 10 months and took it to the dealer to have it fixed. They did a test on the batteries and found both to be bad so they replaced both batteries with new ones. About a month later I upgraded to 11.0.7 and two days later my batteries are completely dead. I immediately unmarried the tazer and removed it. I used a smart charger to charge the battery back up overnight. A week of ESS working perfectly, I decided to reinstall the tazer just for the Cargo Cam, Tire Size and TPMS using 11.0.6. I then removed the tazer but kept it married. I've been driving like this for a few weeks now but it did make me wonder what the actual parasitic draw was on these jeeps.
Very interesting! I had my Tazer married & installed until last Saturday. I adjusted TPMS, tires size, the feature that allows me to use the fog light with high beam, in motion nav, and ESS. I believe that all. Using the same firmware, 11.0.6. @WranglerMan is doing a lot of testing, so hopefully he’ll be able to figure out something. I’m just curious what my dealership is going to say once they figure it out.
 
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RussJeep1

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Warning! DO NOT disconnect the negative battery cable from the ground and then place the multi-meter in between. This initial hit spikes over 10A and will blow the multi-meter fuse. I tried that 4 times before I figured out a better way. The damn fuse is not easy to replace in those meters!

1) Remove this nut but leave the wire on. This is the ground for both batteries.
Step1.JPG


Set up the Multi-meter:
1) Set to Amps DC. Mine is automatic. If yours is not automatic then start with something larger first like 100A and then work your way down.
2) Make sure it says it is for DC not AC
3) Switch the red wire from 'INPUT' to '10A'
Step2.JPG


Connect the multi meter leads:
It is important that you do this while the negative battery wire is still connected to the ground! This is because the first connection of the negative battery wire to the ground spikes the current draw over 10 amps and blows your multi-meter fuse. I don't know why this is but I blew 4 fuses in my multi-meter before I came up with this way to get around the initial spike.
1) Connect the red multi-meter lead to the negative cable
2) Connect the black multi-meter lead(now a green alligator clip)
3) Push the negative cable off the bolt to begin the readings on the multi-meter

By doing it this way the negative cable always remains connected to the ground in on form or another.
Step3.JPG


My parasitic draw was 134 mA: (ignore the negative, I had the leads reversed the first time)
10minutes.JPG


Playing around, I disconnected the multi-meter, disconnected the negative cable to the ground which cut the power to the Jeep. I then put the negative cable back on making sure it grounded but no nut. I quickly reattached the multi-meter and then pushed the negative cable back off the bolt.

This resulted in a 4.9 Amp reading initially and quickly dropped down to around 2.5 Amps. After about 30 seconds the current dropped down to 1.5 Amps and stayed there for 5.5 minutes. It then dropped to 230 mA. After around 20 minutes I get around 140 mA.

I really appreciate that you shared this.

As a matter of context sir, the only thing I am deliberately aware of that would drain my batteries is a dash cam that continues to record when the rig is parked, albeit in a lower electric draw mode that is designed to stop filming when (combined) battery voltage drops below the highest threshold the device allowed me to set it at: which as 12.4V

Not until I hooked the rig up to a trickle charger was I able to get back ESS, despite no error messages. This has been since this summer that it stopped: an April purchase. I will take the rig for service while its still under warranty. I'd love to know the electric thresholds, all other ESS stopping reasons notwithstanding (e.g. engine still cold) the computer decides to not engage ESS at.
 
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I really appreciate that you shared this.

As a matter of context sir, the only thing I am deliberately aware of that would drain my batteries is a dash cam that continues to record when the rig is parked, albeit in a lower electric draw mode that is designed to stop filming when (combined) battery voltage drops below the highest threshold the device allowed me to set it at: which as 12.4V

Not until I hooked the rig up to a trickle charger was I able to get back ESS, despite no error messages. This has been since this summer that it stopped: an April purchase. I will take the rig for service while its still under warranty. I'd love to know the electric thresholds, all other ESS stopping reasons notwithstanding (e.g. engine still cold) the computer decides to not engage ESS at.
I just purchased a blackvue ultra battery pack and now run my dash cam off of it instead of the main battery. This gives me 20 hours of parking mode for the dash cam. Did you know that when your main battery is down to 12.4 volts that it is 25% depleted? That is not something I wanted to do on a daily basis. These jeeps have enough parasitic draw without adding a dash cam in park mode.

If your evic battery charger is always over 14 volts it might be worthwhile to have your dealership do a battery test with load. It’s the only true way to detect a bad battery.
 

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I just purchased a blackvue ultra battery pack and now run my dash cam off of it instead of the main battery. This gives me 20 hours of parking mode for the dash cam. Did you know that when your main battery is down to 12.4 volts that it is 25% depleted? That is not something I wanted to do on a daily basis. These jeeps have enough parasitic draw without adding a dash cam in park mode.

If your evic battery charger is always over 14 volts it might be worthwhile to have your dealership do a battery test with load. It’s the only true way to detect a bad battery.
Thanks for the head's up on the meaning of the 12.4 volts that I know I never got anywhere close to. Maybe I too should get a battery pack. I'm just not sure I can configure my camera to, while in park mode, fall back on the rig's power when said optional camera battery pack is depleted.

I assume it charges when the rig is on, hooked up to an accessory wire...i.e. one only energized with the starter button in the "on" state. If so, I wonder how long it takes to charge.

It may be over kill for me. I usually park in my driveway at night where power is readily available to plug in my trickle charger: always under the dash with its AC cord accessible from outside the rig. Still more I'm a short trip driver that offers relatively little crank time to charge things tapped when the rig's parked.
 
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Thanks for the head's up on the meaning of the 12.4 volts that I know I never got anywhere close to. Maybe I too should get a battery pack. I'm just not sure I can configure my camera to, while in park mode, fall back on the rig's power when said optional camera battery pack is depleted.

I assume it charges when the rig is on, hooked up to an accessory wire...i.e. one only energized with the starter button in the "on" state. If so, I wonder how long it takes to charge.

It may be over kill for me. I usually park in my driveway at night where power is readily available to plug in my trickle charger: always under the dash with its AC cord accessible from outside the rig. Still more I'm a short trip driver that offers relatively little crank time to charge things tapped when the rig's parked.
Actually the dash cam always runs on the battery pack now. The battery pack gets charged from the main battery when the ignition is on. If you have the auxiliary switches then you have a wire already available that is power only when the ignition is on. The wire is only rated for 10 amps and I already have my off-road camera and CB connected to it so I had to buy a relay and bring power from the battery. It was a pain to set up but I am happy I have it now.

Edit: it takes 40 minutes to charge and lasts 20 hours when vehicle is off. You can daisy chain more battery packs to keep multiplying the number of hours it lasts.
 

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@TroyBoy I have not checked my JL for a parasitic draw but may do so, at this point in almost 14 days of taking daily voltage readings on my JL I am not seeing any significant differences in leaving the Tazer plugged in versus leaving it unplugged.

I am running the original Tazer Jl with the secondary SGW module along with firmware 11.06 and have changed the following

Vehicle settings:

Tire size changed
TPMS alarm limits changed
Fog light drop changed

Live settings changed:

ESS is the only feature I am using from the live side

The first 7 days my voltage averages were

12.62 Main
12.62 N1
12.62 N2
13.1 EVIC
12.58 ESS

And the hi/ low reads were

12.67-12.56 Main
12.67-12.56 N1
12.67-12.56 N2
13.9-12.6 EVIC
12.62-12.48 ESS

And so far with the Tazer plugged in they are looking to be approx the same but with a few small differences as in the day 1 voltages were slightly higher even though I waited several hours after coming off the tender to take them and on day 5 without the Tazer in and day 3 with it in I saw elevated evic voltages in the 13.8-13.9 range and have no idea why

I have tested ESS at every opportunity I have and all seems to function as designed so again I’m stumped, it’s very possible that a lot of us have had just bad batteries or that there is a glitch in 11.07 which I’m not going to use at this point, my thought is after tomorrow and I go thru my numbers again is to unplug the Tazer and not utilize disabling ESS and monitor my EVIC voltage and just take 3 voltage readigs a week ( Main, ESS and EVIC) and see if there is any difference in the condition of my batteries but I’m thinking there’s not going to be much of a difference
 

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My parasitic draw was 134 mA:

This resulted in a 4.9 Amp reading initially and quickly dropped down to around 2.5 Amps. After about 30 seconds the current dropped down to 1.5 Amps and stayed there for 5.5 minutes. It then dropped to 230 mA. After around 20 minutes I get around 140 mA.
I think you should revisit this measurement and wait longer for the vehicle to fully go to sleep. Even the heavy duty 75 Ah battery is brand new in PERFECT shape at room temperature, with a 134 mA parasitic draw your battery would be stone cold dead if the car sat for:
75 Ah / (0.134 Amps x 24 hours) = 23.3 days. And most batteries are not in perfect shape.

I think the actual parasitic draw is about 30 mA. This gives 75 Ah / (0.30 Amps x 24 hours) = 104 days.to a dead battery.
 
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I think you should revisit this measurement and wait longer for the vehicle to fully go to sleep. Even the heavy duty 75 Ah battery is brand new in PERFECT shape at room temperature, with a 134 mA parasitic draw your battery would be stone cold dead if the car sat for:
75 Ah / (0.134 Amps x 24 hours) = 23.3 days. And most batteries are not in perfect shape.

I think the actual parasitic draw is about 30 mA. This gives 75 Ah / (0.30 Amps x 24 hours) = 104 days.to a dead battery.
So just tried it again and my parasitic draw was 129ma for the first hour. After that it dropped to 11-18ma with the occasional spike to 70ma.
That is much better.

@SmartStopStart.com Does your device have any parasitic draw? Also, when you say 104 days to a dead battery do you mean 100% depleted? I don't think it is healthy to draw a battery down less than 30% depleted.
 

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So just tried it again and my parasitic draw was 129ma for the first hour. After that it dropped to 11-18ma with the occasional spike to 70ma.
That is much better.

@SmartStopStart.com Does your device have any parasitic draw? Also, when you say 104 days to a dead battery do you mean 100% depleted? I don't think it is healthy to draw a battery down less than 30% depleted.
Yes, 11-18 mA sounds correct. The 70 mA spikes will then raise the average slightly.

SmartStopStart draws approx. 1/4 of 1 mA (0.250 mA) when sleeping with ignition off, which is virtually insignificant.

Correct, a wet Lead Acid battery should spend its life as close to fully charged as possible or the life will be severely shortened.
 

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This is an interesting thread, and just wanted to add that my findings are identical, as far as initial amperage being at 5 amps when battery is first connected, and gradually decreasing over time to about 150ma.

I haven't seen it drop below that point yet, so I'll check back in an hour or so to see if it drops down into the below 20ma range.

I should note, I do have a Tazer connected.

Thanks for the informative post. I've been looking into this quite a bit as I troubleshoot some issues I've been having with my Odyssey batteries in the Genesis dual battery system.
 

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