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-   -   Gremlins? (https://www.hummerforums.com/forum/hummer-h3-17/gremlins-41565/)

dwaller67 06-29-2019 05:24 PM

Gremlins?
 
The site won’t let me upload the video. I’ll try later.

hummerz 06-29-2019 08:45 PM


dwaller67 06-30-2019 05:44 PM


dwaller67 06-30-2019 06:02 PM

I had been out running some errands, the car was running fine. I left the AT&T store and went out to the car and it started fine. I put it in drive. The windshield wipers came on and the car shut off. I removed the cover over the BCM because I heard a faint buzzing. I tried starting the car again. It would start and run but it would not allow me to put it in drive. I had my scan tool with me so I ran the codes. There were a bunch of them. I cleared the codes. Around this time I shot the video. By now the car would not run, it would only start then die. I ran/cleared the codes again and now the car would start but not remain running once put into gear. I revved the engine and tried shifting to neutral. Didn't work car died. I revved the engine again and turned on the wipers (since they had a mind of their own now). The voltage would drop from 15.5 VDC to 11 something and the car would start to die again. So I used the list of codes (everything it said was showing HIGH) and pulled the relays from under the hood. Front headlamps, high beams, interior lights, and finally the relay for the wipers. As soon as I pulled the wiper relay the car shut off. I started the car again and everything was fine. I replaced the relays and drove home. Drove it today with no issues.

hummerz 06-30-2019 06:15 PM

4v drop is a major short somewhere. go back and clean/lube connections and inspect the wiring. GL

dwaller67 07-07-2019 12:25 PM

Everything is pointing to the high beam / low beam / turn signal switch. Anyone ever changed one of these out? All the videos i can find on YouTube show the key on top of the steering column, not under it. The replacement switch has a doughnut hole in it so I am guessing I will have to pull the steering wheel.

hummerz 07-08-2019 03:37 PM

10 Attachment(s)
Hopefully you checked the wiper motor/connector/wiring, +check wiring to the multifunction switch before you replace. GL

Disconnect negative terminal.

dwaller67 08-03-2019 10:22 PM

The problem ended up being the ignition switch.

I parked the car for a few weeks and went over the events as they happened. The smoking gun for me was pulling the wiper relay and the car shutting down. Electricity always seeks the path of least resistance. So if I have a closed signal through the ignition switch then why is the current back feeding through the BCM and wiper relay?

I pulled the old switch out and noticed pins 2 and 4 were dark (indicating higher current than the switch was designed for). Pin 2 is the positive rail to the switch and pin 4 leads back to the BCM for the crank/run signal. I replaced the switch and I have had no more events.

I'll add to the post later if things go south but I think I have found the main cause of the current issue.


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