Electrical demon

[hufhouse]

I posted this in the Pontiac Montana forum, but got no response, so I thought I would come over here and see if you guys had any ideas. I noticed the sticky at the top about the PSD diagnostics, and I'll be trying those later.

2000 Montana

In one single trip, my power sliding door, rear window wiper AND automatic locks (when putting the car in Park and in gear) stopped working. (The automatic locks work...they just don't lock the car when you put it in gear or unlock the car when you put it in Park.)

This is too much of a coincidence to be three separate problems.

However, I can't find any common relationship between the three at the fuse box.

I tried the reset procedure for the sliding door to no avail.

Could this be a bad BCM? There's a possibility that I fried something, because I repaired the ground wire on the left rear indicator lights by completely bypassing the plug and soldering everything together. The ground connection of the plug had essentially melted away. When I did that, I accidentally had a little drop of solder shorting between two of the connections. When I found the lights didn't work correctly, I looked at my solders closely, repaired the connection, and everything in the rear lights works perfectly. That was a day or two before this electrical problem occurred.

But, now I have these three NEW problems.

Any ideas?

[dewaynep]

I'm just stabbin' in the dark here, but do all of those connections go through the pass-through connector under the vehicle behind the drivers seat? I don't have the wiring diagram in front of me, but you may have fried the ground to all of those systems at the same time?

[hufhouse]

I ran the first part of the PSD diagnostics, and there are no trouble codes stored.

What would I be looking for with that bad ground? Is there some kind of plug or connector that's bad?

Here's another little clue...my wife jiggled the rear wiper a little bit and it went down by itself. We haven't had the guts to try it again. :-) So, it's obviously getting power.

I'm going to try reprogramming the locks to lock automatically when the car goes into gear. Maybe it just lost the programming.

The PSD seems as dead as a rock. No noises...nothing to indicate it's even trying to open or close the door.

[hufhouse]

I figured it out, but have a new problem.

The Backup Light fuse was blown. That caused the door and lock problems. The rear window wiper seemed to fix itself.

However, now I can't figure out why I can't keep the backup light fuse from blowing.

I bypassed the plug to the left rear turn signal because the ground connection had corroded away. I just matched the wires up to the pins and soldered it together.

Now, I keep blowing backup light fuses. I checked and re-checked my solders and even re-soldered them tonight very cleanly.

Any ideas?

[lesterl]

Could be a bad transaxle range switch or sumtin, check out the wiring diagrams on www.autozone.com the circuit for the BU/L is pretty basic.

[hufhouse]

I kind of think I fried the circuit board somehow when I had the little drop of solder between two of the connectors. I bought a new circuit board on eBay. I'm also checking online at different scrapyards to see if I can just get a used wiring harness with a usable plug.

[cjstew4]

Originally Posted by hufhouse

I kind of think I fried the circuit board somehow when I had the little drop of solder between two of the connectors. I bought a new circuit board on eBay. I'm also checking online at different scrapyards to see if I can just get a used wiring harness with a usable plug.

Pull up the front carpet on the pass side to reveal hopefully a dry wire harness bundle. If it is wet, the A/C drain hose may have fallen off the firewall causing any drainage inside and under the black mat,etc to then settle in the harness channel. If it is dry, I would still unwrap most of the harness and observe the shoddy crimping, etc., lack of acceptable connections with some risted. This harness is key to most of what is powered from the front seats back, including the diver's side power seat controls. I put new connections on as much as I could and it solved a few issues that were not even throwing codes.