just put in a 82 Datsun ZX alternator in my 1975 280Z. Did the proper jumper wires to eliminate external voltage regulator. Car starts but volt meter reads on the negative side. Any suggestions?

Asked by Jul 25, 2015 at 12:31 PM about the 1975 Datsun 280Z

Question type: Maintenance & Repair

2 Answers


Check voltage with a hand held voltage tester if charging at 14 volts you have a bad gauge and if its not you have a bad alternator or that alternator that you installed is charging at the wrong voltage. Maybe be a different voltage alternator from the 82 Datsun for your 75 280Z.


IS IT ENERGIZING ?IS THERE A IDIOT LIGHT IN THE SYSTEM..The yellow wire is the Sense, or S, wire. It monitors voltage so that the internal regulator will work correctly. Without it connected, I think that the alternator might put put maximum voltage (once you get the L wire connected). It has power all the time.

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