Need a 87 suburban wiring diagram

[danomano]

Your drawing is simular to what I have. It shows the red tied back to red but mine does not. I think this on goes back to the voltmeter on the dash. and the brown is the ground for the other circuit. Which reads open on both pins. One side show be ground and the other should put out 12volts. NAPA was out of my alternator( lifetime warranty) but might have to goto autozone and get one.

I took the truck to the dealer to check why the alternator was dead and they said it was from the butt connector the when from the positve side of the battery to the alternator's lug terminal. They crimped and solder the connection and replaced both connections at the battery. I realy don't see how this killed the alternator though? What part of the circuit tells the alternator to turn on? Is there a self starting one the does not need to check battery voltage? Could grounding out 12volt out on 1 or 2 (forgot which one ) kill the alternator?

[wildmanaaron]

If the diagram posted does not work, go by the local GM dealer and ask a Tech if they will print one off for you. I bought a GM service manual for my 1981 Blazer since I was redoing a lot of the original wiring and it was the best source for schematics. Alot of the diagrams like the one posted come out of the Haynes books aren't correct a lot of the time.

[Mkcustums]

Originally Posted by wildmanaaron

If the diagram posted does not work, go by the local GM dealer and ask a Tech if they will print one off for you. I bought a GM service manual for my 1981 Blazer since I was redoing a lot of the original wiring and it was the best source for schematics. Alot of the diagrams like the one posted come out of the Haynes books aren't correct a lot of the time.

I found my book and it shows the wiring different than shown above. It's a GM service book, very detailed. I just don't have the scanner hooked up to get the info to you.

I have gone to dealerships and had them print off stuff for me as well.

[danomano]

Maybe figured this one out it seems the alternator turn on comes from the computer. If the computer is not working then that is why only battery voltage. When I bought the turn I remember checking for codes and it would only give me "12" some maybe to computer died.

[danomano]

Forget that I found another person that had the exact same problem and here is what he did.

http://www.automotiveforums.com/vbul...d.php?t=751508