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Wiring frustration, lights.

1819 Views 12 Replies 7 Participants Last post by  scooter10572
Alright I don't know where to start so I'll just spill it. '99 S10 PU 2WD RC SB 2.2 5SPD.

All problems seem to be rear passenger side.

Lights on, all good.

Lights on + reverse = No passenger reverse light, no passenger license plate light.

Lights off + reverse = Reverse light on license plate light on.

Lights off + drivers side blinker = All good.

Lights off + passenger blinker = Blinker blinks with license plate light.

Lights on + drivers side blinker = all good.

Lights on + passenger side blinker = Blinker blinks with license plate light / both blink fast.

I removed rear harness from truck and stripped of all the loom. I inspected the wiring, found nothing. There is only one ground for the entire rear harness, it's good.

I did find something on on the drivers side blinker socket. It looked like it got hot at one point. Someone spliced in some wires there that I assume would run a third brake light on a topper. I removed the wires. That socket always worked and still does.

Re-wrapped the harness and reinstalled it. Nothing has changed.

Is the problem with the blinker switch or what? I'm out of ideas.

P.S. Does anyone know what those odd looking connectors on the rear harness are for? I can't imagine what they'd ever be used for.

Thanks for any help,
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I fixed it.

I went to the library and looked up the wiring scematic. I stared at the computer screen for a good thirty minutes. Computer said two grounds, I was sure it was wrong.

Seems when the people who had the truck before me replaced the box they messed up two grounds. One for the fuel pump/drivers side of the rear wiring harness, which I was painfully aware of. And the ground for the passenger side of the wire harness. I found a neatly snipped wire right at a connector that I had overlooked earlier.

I feel better now, thanks for the help.
Thankfully, when they did their hack work, they did it neatly! :yup:
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