mrschwarz
Member
- Thread starter
- #1
I have a 21 JLU Rubicon. The ESS light came on a year ago, but I ignored it because everything else was working and I assumed it was the aux battery and ESS wasn't important enough to get it fixed. I had replaced the main battery about the same time, before I even knew about the second one.
I also flat tow the jeep so I pulled one of the LED sense wires out of each tail light so the lights from the tow vehicle wouldn't trigger the BCU to turn on. It resulted in the inside turn signal arrows blinking twice as fast and a message on the dash that the tail lights were out (they weren't) whenever I started the car.
I am getting ready to trade the Jeep in so I thought I would do the aux battery bypass and reconnect the LED sensors in the tail light. This morning, I opened the hood, pulled the F42 fuse and disconnected, what I thought was the aux battery negative. I turned out I disconnected the wrong negative wire. The car would start and the dashboard was dead. I reconnected the negative wire and disconnected the other one. The courtesy lights then came on and the dashboard woke up when I opened the drivers door.
The engine started, the ESS light didn't turn on and the turn signals started blinking at their regular speed again. I put the car in reverse and got a message on the screen that the camera system was not available. Also, the seat heaters and steering wheel heater came on. The AC was set to 'LO' instead of whatever temperature it had been set to.
I shut it off and reconnected the second negative cable, which I assume is the negative to the aux battery and restarted the car. The rear camera started working, but the turn signals still didn't indicate they were out and and the AC was still stuck on 'LO' instead of letting me set the temp. I shut it off and reinserted the F42 fuse. The result was the same.
I don't know if it matters, but the hood was open the whole time.
Any ideas what's going on? How do I recover?
I also flat tow the jeep so I pulled one of the LED sense wires out of each tail light so the lights from the tow vehicle wouldn't trigger the BCU to turn on. It resulted in the inside turn signal arrows blinking twice as fast and a message on the dash that the tail lights were out (they weren't) whenever I started the car.
I am getting ready to trade the Jeep in so I thought I would do the aux battery bypass and reconnect the LED sensors in the tail light. This morning, I opened the hood, pulled the F42 fuse and disconnected, what I thought was the aux battery negative. I turned out I disconnected the wrong negative wire. The car would start and the dashboard was dead. I reconnected the negative wire and disconnected the other one. The courtesy lights then came on and the dashboard woke up when I opened the drivers door.
The engine started, the ESS light didn't turn on and the turn signals started blinking at their regular speed again. I put the car in reverse and got a message on the screen that the camera system was not available. Also, the seat heaters and steering wheel heater came on. The AC was set to 'LO' instead of whatever temperature it had been set to.
I shut it off and reconnected the second negative cable, which I assume is the negative to the aux battery and restarted the car. The rear camera started working, but the turn signals still didn't indicate they were out and and the AC was still stuck on 'LO' instead of letting me set the temp. I shut it off and reinserted the F42 fuse. The result was the same.
I don't know if it matters, but the hood was open the whole time.
Any ideas what's going on? How do I recover?
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