Alternator Post Grounded? Help. - Third Generation F-Body Message Boards

usa1racing · 09-06-2005, 10:42 PM

Need some help wiring up from scratch. If I put an ohm-meter lead on the alternator's main post where the main power wire connects to, and the other lead to the alternator case, the resistance goes down to approximately 275 ohms. The battery is grounded to the cylinder head, and also to the passenger inner fender. There is also a ground strap from the intake manifold to the firewall. I've included a schematic. It seems as if the main power post on the back of the alternator is grounded. I can hook up the battery if the main power wire off the back of the alternator is connected, but it short circuits whenever the wire is connected. Any ideas?

Trickster · 09-06-2005, 11:32 PM

Basically what you are doing is OHM'ing out the alternator and yes you will get resistance, you are supposed to. You can get resistance by touching the alternator case and practically any part of that car because they are connected by the grounds. If your car is the 1988 camaro that you have listed in your profile, here is the schematic of how your wiring is supposed to be.

usa1racing · 09-07-2005, 12:43 AM

Problem solved. I had it wired up right, but I was getting a huge spark whenever I touched a battery cable to a post. It would be akin to trying to hook up the main power lead off the back of the alternator with the voltage regulator turned on, and the battery still connected. Thanks for the picture.