Stick with me. This might be a bit circuitous, but I'll get there. Since I bought this truck I've been chasing electrical gremlins. There seem to be three of them and every time I fix one thing the gremlin takes up residence someplace else. For instance, my horn, cigarette lighter plug, and cruise control all started malfunctioning on the same day. It would be logical to assume these failures were related to a common problem, but after troubleshooting I discovered they were independent issues. That's the problem with having three gremlins. If I isolate one variable there always seems to be two other unknowns. Most recently I took a trip and the gremlins went wild.
This started immediately after i "fixed" my exhaust (It's in another thread O2 sensors on custom exhaust) and cleared the CEL. When I stepped on the brakes, my dash lights came on. Strange mystery. How is this related to the CEL? (It wasn't) I started chasing grounds. Eventually, the brakes would turn on a turn signal. Then the other turn signal. Then the diff lock light came on but went out when I touched the brakes. Then the brakes caused the turn signals to stop working. Then the rear wiper started coming on unexpectedly. Then the ABS started to malfunction. Eventually, I lost all tail and marker lights while I was on the interstate in a snow storm at night, and had to be towed.
I chased every relay, every fuse, poured over the EWD, chased every ground and couldn't find the problem. All the relays worked and no fuses had blown. Moreover, I didn't know if these problem were causally related or just correlated. I couldn't even find anyplace where all these systems overlapped. In case you're wondering and want to skip to the end; The problem was... the fender flares.
Or more accurately, the fact that I had removed them.
I'll get to it. After chasing everything I could possibly think of I decided to start isolating symptoms and troubleshooting independently. The signals, brakes, and dash lights all seemed like a problem with the trailer connector so I started chasing those wires. The trailer connector was fine but in my search I found this...
That is, according to the EWD, the BQ1 connector in the drivers quarter panel, and yes... it has been on fire.
Apparently, when I deflared the truck I exposed a rust hole and was allowing salt, water and snow to splash into the quarter panel corroding and eventually shorting the connector and causing havoc. I was extremely lucky my truck didn't catch fire because the factory toolkit and my jumper cables are stored just above this connector and that is enough plastic that it could have caused a hell of a fire, not to mention this is all right next to the fuel filler.
Anyway, I'm not entirely sure what the lesson is here, but I'm sure there is one and I'd be happy to hear it. Just wanted to share.
This started immediately after i "fixed" my exhaust (It's in another thread O2 sensors on custom exhaust) and cleared the CEL. When I stepped on the brakes, my dash lights came on. Strange mystery. How is this related to the CEL? (It wasn't) I started chasing grounds. Eventually, the brakes would turn on a turn signal. Then the other turn signal. Then the diff lock light came on but went out when I touched the brakes. Then the brakes caused the turn signals to stop working. Then the rear wiper started coming on unexpectedly. Then the ABS started to malfunction. Eventually, I lost all tail and marker lights while I was on the interstate in a snow storm at night, and had to be towed.
I chased every relay, every fuse, poured over the EWD, chased every ground and couldn't find the problem. All the relays worked and no fuses had blown. Moreover, I didn't know if these problem were causally related or just correlated. I couldn't even find anyplace where all these systems overlapped. In case you're wondering and want to skip to the end; The problem was... the fender flares.
Or more accurately, the fact that I had removed them.
I'll get to it. After chasing everything I could possibly think of I decided to start isolating symptoms and troubleshooting independently. The signals, brakes, and dash lights all seemed like a problem with the trailer connector so I started chasing those wires. The trailer connector was fine but in my search I found this...
Apparently, when I deflared the truck I exposed a rust hole and was allowing salt, water and snow to splash into the quarter panel corroding and eventually shorting the connector and causing havoc. I was extremely lucky my truck didn't catch fire because the factory toolkit and my jumper cables are stored just above this connector and that is enough plastic that it could have caused a hell of a fire, not to mention this is all right next to the fuel filler.
Anyway, I'm not entirely sure what the lesson is here, but I'm sure there is one and I'd be happy to hear it. Just wanted to share.
