I was wondering if there was anyway of testing a voltage regulator while it was on the car. Anyone have an answer?

 

There are two things you can do to test teh regulator. You can meter the output voltage under various loads. A battery load tester can be very helpful when doing this, but you can also use the vehicle accessories to load the system.

If the alternator output voltage remains relatively steady under varying loads, teh regulator is at least attempting to maintain a steady output voltage.

Another thing you can do to test the alternator more than the regulator, is to shunt the regulator and test alternator maximum output. You can do this by shorting the test terminal on the rear of the alternator while metering output voltage. Only do this briefly, since hte voltage will probably reach around +18.

 

Thanks Vader,

It wasnt the regulator. Its fixed and working fine now a alternator overhaul for 40 dollars. Beats the 100+ and I know what I have.