Re: Engine dies when headlights are turned on

Posted by Owen_Dyneto On 2011/11/22 12:09:09

Forgive me, I haven't carefully followed what's gone on in the past with this problem, but have you performed the most basic of tests?

I assume your car does not have an ammeter. Attach a voltmeter across the battery with the engine running and an electrical load applied (headlamps for example), read the voltage. Then accelerate the engine modestly and measure the voltage again; Compare before and after readings.

Do the same thing again but this time with a temporary jumper wire grounding the Field terminal of the regulator.

In the first case the voltage probably dropped to about 6 volts or slightly less (a well-charged lead acid battery at rest should read about 6.6). If the voltage didn't increase to about 7.5 (+/- a few tenths) your charging circuit is not functioning.

In the second test, if the voltage now increases, the problem is the regulator and not the generator. DON'T leave the jumper connected for longer than needed to perform the test.