Take Two

[cjsgarage]

I couldn't sleep knowing I wasn't sure. I looked it up. The brown wire is indeed the wire that goes to the alternator light, but it comes from the regulator. The two wires coming from your alternator (as best I can make it out) are R and F. R is for relay, but it's basically a "sense" wire. It checks for voltage drop, so it knows how high to kick up alternator voltage. F is for field. It's basically the control for voltage.

F goes to terminal #1 on your regulator.
R goes to terminal #2 on your regulator.

Double check those bad boys with a Ohm meter right quick. Sould be under 5 ohms end to end, disconnected from their connectors.

Terminal #3 on your regulator should go to battery power.
Terminal #4 on your regulator should be the brown wire that goes to your gauge.

Again, check those with an ohm meter. It might not be so easy to check the brown wire to the back of the gauge cluster.. so maybe you'll get lucky and find the problem in the first three wires. Or a regulator will fix it.


I always replace regulators and alternators together, too. Seems like I can't keep them from coming back unless I replace both.

[cjsgarage]

oh yeah. To test your alternator, jump the blue wire to the battery post with the engine running. Your alternator should output as high a voltage as it can.

I have more tests to check the wiring and regulator if you get that far and haven't narrowed it down yet.