How do I check if the voltage regulator has packed up? I don't have a spare but I know the car isn't charging?!

Any ideas?

Thanks

Tim

Would you not be looking at if the alternator is charging first, check the belt tension and wire connections then with the car not running put a multimeter across the battery terminals ,should read about 12.5 if healthy then with the car running do it again ,should read about 14.5 if the alternator is doing its job.

was working fine as far as i know. charging both batteries ok. Terminal clean and fitted correctly. Battery reads same voltage with or without engine running. Fuse to 2nd battery fine and relay switch operating fine.

Last time it failed it turned out to be the voltage regulator, just wanted t know how to test this one?!

Until someone who really knows what they're talking about turns, up I'm going to say switch the ignition on, and check that the small wire is delivering power to the alternator. That power comes via the voltage reg, which switches it on and off to control the alternator output.

No power on that wire and the alternator won't be doing anything. Continuous power on that wire and it will be over charging.

(Edit, I should just add that there's no easy way of monitoring that power going on and off, it happens to quickly, you can only check that it's on once you switch the ignition on, and stays on while the engine's idling.)

if its an old electro mechanical one do a continuity test over the three wire resistors on the bottom, all should have the buzzer going to a degree, then check the voltage at the lucar connector that goes to the alternator that should have something. If all thats ok it may just be the brushes in the alternator

You say you don't have a spare Tim but, can't you "borrow" the one off D*lly for testing purposes?

I'm guessing it is the D*lly, and the AK's got a GSA alternator with internal reg.

As far as I'm aware, D*lly doesn't have twin batteries etc that Tim is referring to!

<cough> I read that as having swapped batteries between the two...

Oi, you at the back-Chapman, pay attention boy!