Service Stop/Start System Warning Light - P2AF6

303rider

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Having the same issues. Warning light coming on.
My dealer told me it was due to a low battery. They charged it and it worked for a bit. Coming back on once a week.

My theory is the secondary battery is not holding a charge.
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tCub

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If the warning light comes on immediately when starting the Jeep, try this -

  1. Shut the Jeep off
  2. Unplug driver door wire harness (behind kick panel, as if you were taking the door off)
  3. Start up Jeep - if the warning light still appears...
  4. Shut the Jeep off
  5. Unplug passenger door wire harness (behind kick panel, as if you were taking the door off)
  6. Start up Jeep

If the warning light does not appear when a door is unplugged, inspect the male pins in the in connector inside the kick panel compartment (the wire harness attached to the door is female).

It may be difficult to see so use your phone to take a picture so you can see it better. One of the pins can easily bend when plugging in the door - it will still plug in with the pin bent, but ESS will fail immediately at start up. If you find a bent pin, carefully bend it back into place.

If you don’t see any bent pins but the process above still results in the warning light NOT coming on, have your dealership replace the wire harness (they can follow the above process to confirm).

For me, ESS hasn’t worked right since I got the Jeep a year ago and it’s been in several times. I’m going to switch dealers soon - long story but relates to the above process, which I figured out on my own (dealer could not). Mine works great but after so many stop/start cycles, the warning light appears. They charged and replaced the battery but that didn’t work. Saga continues for me.. hopefully for some of you, it’s as simple as a bent pin.
 

JeepCares

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Having the same issues. Warning light coming on.
My dealer told me it was due to a low battery. They charged it and it worked for a bit. Coming back on once a week.

My theory is the secondary battery is not holding a charge.
Hello 303rider,

Are you thinking of going back for another inspection? Send me a direct message as we'd be glad to discuss this further and help however we can.

Jasmine
Jeep Social Care Specialist
 

TaiMc

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If the warning light comes on immediately when starting the Jeep, try this -

  1. Shut the Jeep off
  2. Unplug driver door wire harness (behind kick panel, as if you were taking the door off)
  3. Start up Jeep - if the warning light still appears...
  4. Shut the Jeep off
  5. Unplug passenger door wire harness (behind kick panel, as if you were taking the door off)
  6. Start up Jeep

If the warning light does not appear when a door is unplugged, inspect the male pins in the in connector inside the kick panel compartment (the wire harness attached to the door is female).

It may be difficult to see so use your phone to take a picture so you can see it better. One of the pins can easily bend when plugging in the door - it will still plug in with the pin bent, but ESS will fail immediately at start up. If you find a bent pin, carefully bend it back into place.

If you don’t see any bent pins but the process above still results in the warning light NOT coming on, have your dealership replace the wire harness (they can follow the above process to confirm).

For me, ESS hasn’t worked right since I got the Jeep a year ago and it’s been in several times. I’m going to switch dealers soon - long story but relates to the above process, which I figured out on my own (dealer could not). Mine works great but after so many stop/start cycles, the warning light appears. They charged and replaced the battery but that didn’t work. Saga continues for me.. hopefully for some of you, it’s as simple as a bent pin.

This is great info! My ESS stopped working but it was directly related to my temperature gauge being faulty. I think I have a jacked up sensor somewhere... as fan comes on and is really loud trying to cool the engine, but the engine is not hot. Mechanic believes it is either a software prob, or the sensor not reading and giving Engine controller the wrong info. Will find out soon! So glad you posted these steps! Thanks!
 

D-Mo

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I also had the service start/stop system light coming on and mine was traced back to a malfunction in the door latch. I was able to track it down by unplugging the wire harness for the door and that turned the light off.

Going in tomorrow to replace a door latch causing the same (service autostart system) alert to pop up. Did replacing the latch work for you?
 

303rider

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I took it to the dealer. They replaced a control unit for the ESS system. The warning light stayed off for 3 days LOL. Some fix.
I noticed if it comes on, I can simply stop start the jeep again and it wont always show back up. Not sure I want to waste another 3 days at the deal because they clearly have no idea how to fix this issue.
 

ArchAngel

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If the warning light comes on immediately when starting the Jeep, try this -

  1. Shut the Jeep off
  2. Unplug driver door wire harness (behind kick panel, as if you were taking the door off)
  3. Start up Jeep - if the warning light still appears...
  4. Shut the Jeep off
  5. Unplug passenger door wire harness (behind kick panel, as if you were taking the door off)
  6. Start up Jeep

If the warning light does not appear when a door is unplugged, inspect the male pins in the in connector inside the kick panel compartment (the wire harness attached to the door is female).

It may be difficult to see so use your phone to take a picture so you can see it better. One of the pins can easily bend when plugging in the door - it will still plug in with the pin bent, but ESS will fail immediately at start up. If you find a bent pin, carefully bend it back into place.

If you don’t see any bent pins but the process above still results in the warning light NOT coming on, have your dealership replace the wire harness (they can follow the above process to confirm).

For me, ESS hasn’t worked right since I got the Jeep a year ago and it’s been in several times. I’m going to switch dealers soon - long story but relates to the above process, which I figured out on my own (dealer could not). Mine works great but after so many stop/start cycles, the warning light appears. They charged and replaced the battery but that didn’t work. Saga continues for me.. hopefully for some of you, it’s as simple as a bent pin.
This way my issue. After removing and replacing the doors many times on other JLs, I’m surprised this happened. Here is what mine looks like. See the top left.

42A92DFC-704E-4AEF-B92A-820886BA85A7.jpeg
 
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LincolnSixAlpha

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I'll throw my towel into this to see if it helps. Even though I don't use the ESS system, it's set to turn off on startup via my tazerJL mini, I did receive an error once where they Start/Stop system malfunctioned with the light indicating as such while idling one hot day here in AZ. Shortly thereafter a code was thrown via the computer. The error code did not go away until I cleared it with a tool. The code was indicative of an emissions-related error, specifically something to do with air temp or intake air in some manner.

Few things to note via this point,

  • The air filter was simply full of sand, and all clogged up from multiple offroading events, and the last one was particularly dusty, and a very long day.
  • I was in a holding pattern as the dealer wanted 35 bucks for a replacement OEM filter, I ordered one on eBay for 22 bucks, waiting until it shipped.
  • The engine was surging, or pulling (struggling?) very hard to sit at lights and attempts to deliver a high A/C request due to the heat.
  • This error only occurred at idle, and not while driving.
  • The ESS disabled itself twice as I wait for my air filter, only once did it throw code in the computer requiring a clearing.

Once the new air filter came in, I had on hand both MAF, and Throttle Body cleaner, and cleaned out the entire air intake system after removing all of it, including the IAT sensor (as there is no MAF in the intake tube like my last car).

FWIW some of the dust did get past the filter and was injected by the engine, as I witnessed dust all the way through the intake system right up to, and behind the Throttle Body. Since cleaning all of this, and replacing the filter, no longer does the engine feel like it's surging sitting at a light, and no longer has the ESS system disabled itself, and no further codes.

Just my experience with this system. Keep in mind I live in AZ, so A/C demands are very high right now.
 

tCub

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This way my issue. After removing and replacing the doors many times, I’m surprised this happened. Here is what mine looked like. See the two pins bent, top left.

42A92DFC-704E-4AEF-B92A-820886BA85A7.jpeg
Quite certain that’s it. Try to carefully bend the pins back and attach the connector. Hope that helps! I’m extra careful now when plugging that thing back in. Strange too it only happened to the driver side door.
 

ArchAngel

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Quite certain that’s it. Try to carefully bend the pins back and attach the connector. Hope that helps! I’m extra careful now when plugging that thing back in. Strange too it only happened to the driver side door.
Thanks.
 
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STL J-Hawk

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Going in tomorrow to replace a door latch causing the same (service autostart system) alert to pop up. Did replacing the latch work for you?
Yes, this fixed the issue on mine.
 

jroman

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So was it only a loose wire and bad door latch issue? Both of these lights came up two days ago. The only difference after 1.5 years of driving it was that I recently got an oil change a week before and I was stuck in traffic for approximately 4 hrs on the highway. They've been coming up ever since but do reset when you turn off the vehicle. Nothing different has changed when it comes to driving.

upload_2019-7-9_16-29-54.png

upload_2019-7-9_16-30-12.png
 

STL J-Hawk

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So was it only a loose wire and bad door latch issue? Both of these lights came up two days ago. The only difference after 1.5 years of driving it was that I recently got an oil change a week before and I was stuck in traffic for approximately 4 hrs on the highway. They've been coming up ever since but do reset when you turn off the vehicle. Nothing different has changed when it comes to driving.

upload_2019-7-9_16-29-54.png

upload_2019-7-9_16-30-12.png
They had to replace the entire door latch (drivers side) on mine. That took care of the issue...
 

D-Mo

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Replacing the driver side door latch fixed mine as well.
 

ArchAngel

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My issue is definitely bent pins.
 
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