Well, I need some advice on the charging circuit.
Original problem: I was out with the car for the afternoon and early evening. Started up and turned on the headlights and the alternator light came on, not full bright, but more than just a glow. Turning off the lights dimmed but did not extinguish the light. Got it home with no problem but the battery was well discharged.

Recharged the battery and cleaned connections throughout. Did some voltage checks: 12.57V at the battery posts with the engine off. Started engine and voltage at the battery dropped to 12.43V, this voltage held constant with increasing RPM, but the alternator light did not come on. Pulled the Voltage Regulator and did a field test on the alternator, voltage at the battery increased with increasing RPM, over 16V at 3500 RPM.

Got a new electronic voltage regulator (Bosch 0 192 062 007) from Interpart. Now the alternator light is off at idle but lights more and more brightly with increasing RPM. Voltage measurements: engine off: 12.57V, engine at idle: 13.42V. Only took it up to about 3000RPM and voltage was over 15V.

I figure the new electronic regulator is shorted, allowing full alternator output back to the battery. I’ll try and get them to exchange for another, but, is the 12.43V enough to keep the battery up? I thought it should regulate a bit higher than that.

Thanks,
Harvey

Your voltage readings sound pretty normal. 13.5 to 14 at idle is typical. How high over 15 volts are you getting and what brand volt meter are you using? Also are you saying the charge light is still coming on as you rev the engine?

12.43V is not enough to keep the battery charged. Sounds like the first regulator is hosed. You may be able to open it up and bend the contact arms (like ignition points) to change the voltage; I don't know if this is a permanent solution or not.

The second regulator isn't regulating. It is definitely dead.

--DD

a properly functioning regulator should maintain a battery voltage between 13 & 14.5 volts at all engine speeds.