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When recently doing my auxiliary battery in my 13, I would only get the code for safety systems related to distronic and Eco being disabled. Previously after doing a main battery change, I would have lots of symbols that would pop up initially, but would go away after driving. I did not get as many warnings as you and they were generally related to ESP. I’m not sure if you hooked up a diagnostic, but it will likely register a battery error and you can reset it and see if that gets you anywhere. I know you’ve had a lot of work recently, was your alternator removed and reinstalled at any point?
Fix? I was JRA...parked the car for about two hours. Got back in and this....figured it was low voltage. Tried to jump it...same error. Went and got a new battery. Same. Unplugged rear battery....let it sit an hour or so. Plugged batteries back in....same.
Mechanic is thinking some motor on the trans or a trans resister plate....said to take the blue and white wire out of the CAN (pass foot well) and see if I can scan the car after that....
Fix? I was JRA...parked the car for about two hours. Got back in and this....figured it was low voltage. Tried to jump it...same error. Went and got a new battery. Same. Unplugged rear battery....let it sit an hour or so. Plugged batteries back in....same.
Mechanic is thinking some motor on the trans or a trans resister plate....said to take the blue and white wire out of the CAN (pass foot well) and see if I can scan the car after that....
I see... it's not "battery swap gone wrong !".
The X-Mas Tree started seemingly by itself.
The ISM going into lock-mode is a consequence of low voltage. Let's ignore it for now.
What is your scan report like ??
Do a timely reboot
clear faults
rescan
report
Last edited by CaliBenzDriver; Jun 5, 2025 at 06:04 PM.
The scanner does not see the engine or the trans...moves on to the Dash that says it can not see the engine. Looking at TCU and Trans stuff now (about 45 minutes from the car).
Check the video on post 4....
Last edited by OldManAndHisCar; Jun 5, 2025 at 06:06 PM.
The scanner does not see the engine or the trans...moves on to the Dash that says it can not see the engine. Looking at TCU and Trans stuff now (about 45 minutes from the car).
The scanner does not see the engine or the trans...moves on to the Dash that says it can not see the engine. Looking at TCU and Trans stuff now (about 45 minutes from the car).
Check the video on post 4....
Maybe do a cursory check of the ecu connection to check for oil infiltration? Ive used xentry/das for about ten years so im not sure about how to further diagnose with a foxwell. Im sure you tried to reset but the codes say and stay active. You could ask someone for the wiring diagram from wis or I actually think its called web etm but I cant remember (sorry I dont have connectivity on my system) and see if all of the issues you are having are along one CAN network. If the damage is not something you can literally see, you need to at least find what to test. Xentry usually walks you through the whole process digitally, but the wiring diagram is very simple and concise. there's a few trees and you need to figure out which branch to take.
after watching your third video, are you doubly sure the accessory battery is good. verified with an old fashioned meter?....I think even the transmission pump that is supposed to run during an ecostop is powered from that rear battery. maybe even the fuel pump that is supposed to keep the injectors primed. And did you test the old battery with a meter before recycling it just to see if it was indeed a root cause?
Last edited by Baltistyle; Jun 5, 2025 at 06:45 PM.
In this type of large chaos situation everything is confusing such that it's difficult to sort things out. The modules are confused, we are confused...
One thing leads to another and another... in the end it's hard to understand the root cause. So ppl replace batteries out of convenience.
It seems this involves low voltage
You need to have charged up battery
and good ALT / battery voltage
Once you can rely on voltage then you can wonder what makes modules disfunction... reboot/scan with engine running, not key Off or timed out.
Troubleshooting with scanner data, you should be able to conclude what's wrong.
Can you shift PARK - Neutral - Park with IGN:ON + brakes:ON?
If yes CAN-C is working, ECU/TCU needs SAM Power.
Last edited by CaliBenzDriver; Jun 5, 2025 at 08:15 PM.
Turns out the issue is a transmission Servo motor that is about $800 and requires proof of ownership of the vehicle including driver's license to even order the part
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