Wildly Fluctuating voltage, Christmas tree dash lights, loss of power steering. Solved - I think

[DC3]

I have a '21 gladiator with a November '21 build date that I bout in September of this year. Since day 2 it had weird voltage fluctuations from as low as 8.9 volts and DEF and other warning lights. Every one in a while it would lose power steering, shut down, or go into neutral while stopped. I tried jumping N1 and N2 with an unfused jumper and the issue went away. It returned with a 30amp jumper (blew the fuse)

I researched the potential issues, examined the wiring harness locations, grounds, batteries, etc but could not get the issues to stop. I finally pulled the passenger fender and examined the transmission and engine wiring harness connectors, disassembled, reassembled, etc. While there I inadvertently discovered the start stop relay contacts were not fully tightened from the factory. One of the connections was loose with minor melting of the plastic housing.

So far I am warning light free and I'm sharing because I had not found this issue through my research. I hope this helps someone else save some time.

I realize the Jeep is under warranty and I have an appointment scheduled next week but I don't trust the dealer for electrical diagnostics and figured I would try diagnosing myself.

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[B Mac]

Hi Carl

I see no one responded, so good news is this isn't happening much. Something similar happened to my 2020 JL this past summer.

Let's see,

Voltage drops - check - varied between 12.4 and 14.7 V every 40 seconds or so while driving
Lost power steering - check - not fantastic while you're driving
Christmas light display on the dash - yup

It started with a brake light very occasionally when I was stopped at a red light or a stop sign, and the brakes would start to release. Pretty spooky, but it was months between episodes. It probably had about 18K on it last May when suddenly I started seeing occasional random messages pop up and then go away. In the course of a week, when I was driving the dash went absolutely nuts and I lost power steering right before I was slowing to turn into a driveway.

Fortunately I had a Scan gauge and I was able to reset the codes, there were about 6 or 7 showing at the time. Next stop was a local dealer.

My resolution was the dealer replaced my body control module. Surprised it only took them a day to order one and a few hours to install it. It's been about 7 months or so, 6K mileage or so, and not a single code or problem since. Not sure if they did anything else, but they didn't have it for very long. The only comment the advisor made when I told him I had reset the codes was that it wasn't a problem, I had over a hundred codes on the scanner when they read it at the shop.