So, I am pretty sure my 2000 blazer (4x4 4door LT) wants to catch on fire. I had issues multiply by the day. It started with my back up lights staying on whenever the battery was connected. If you leave the battery disconnected for a while they would stay off for a couple of minutes after the battery is reconnected. They still do that, but now the back hatch glass will randomly unlock. Tonight it decided it wouldn't start and i had no gauges. The 10amp gauge fuse blew, I replaced it and it started and ran and I had gauges. Then it blew again, so I put a 15 in because I am out of 10s. All was good it was starting and running, but now it won't shut off when I take the key out of the ignition. I have to pull the fuel pump fuse. I disconnected the battery and called it a night. Also, I have no P on my PRNDL after replacing the neutral safety switch, but it goes into park just fine.

 

Which of these issues showed up at the same time? I will do my best to help you get this straightened out but its beginning to sound like you gave Linda Blair a ride recently.

George

 

Let me see...
1. back up lights stay on whenever battery is connected, sometimes they turn off on their own after a few minutes.
2. rear hatch glass randomly unlocks
3. alarm goes off every few minutes (I just want to disable this thing)
4. gauges fuse blows, car won't start
5. car starts, won't shut off.

I think that about covers it.

 

I'd check the bottom of the under hood fuse panel and if it looked ok I'd follow the wiring harness to the firewall. Mine was shorted against the abs motor bracket.

 

I might just do that.

 

The only thing common to all of those problems is the underhood fuse block and the initial cable bundle from that block. The only other place that shares many of these problems is the I/P fuse block. I would check under/behind those blocks and the main cables leaving them including the suggestion here of the firewall. The I/P fuse block inside the drivers door can get water corrosion from a leaking windshield or door seal. The underhood fuse block can have many sources of damage hidden from initial view. A cable bundle can hold every wire responsible for this set of problems. Normally I would be suggesting checking grounds but most of these problems are only explained by a short to power. A way to rule out the I/P block is to pull fuses one at a time and see if the back up lights go out. If not then your at or after the UH fuse block and befor the IP fuse block.

George

 

I pulled all the fuses yesterday and nothing turned them off. I forget where I got this but it may be helpful to some. I haven't had a chance to look through the whole thing yet.

https://docs.google.com/file/d/0B9SE...3NjA0NmFm/edit

 

I am looking at a similar set of complete wiring diagrams. If you walk your set of probelms back to their common source of power you see that they are only common to the locations that I mentioned. Did you pull all of the fuses in both fuse blocks?

George

 

Yes I did. I am going to try to find time to pull the under hood fuse box and look for damaged wires this weekend. It is supposed to rain all weekend so it might not happen. I see that the back up lamps and the rear hatch lock both ground to the left rear of the body, so I may start there first.

 

This is not a ground problem, if it were then you would have circuits that would not turn on. A hot wire that is not affected by pulling fuses is making contact with the affected circuits after their fuses but before the loads.

George