<-=- Club Bevel Heaven -=->

hi all!

my '78 darmah seems to have recently developed an issue w/the dashboard lights - the generator light won't go off; and i believe it's still charging - when i went for a ~60 mile ride a couple daze ago w/the headlight on, i stopped twice, no issues restarting, headlight still bright. when i got home, also no issue restarting. i believe it's a wiring issue because the dash headlight indicator stays on, even w/the headlight off. and once or twice, while riding, i noticed the generator light briefly went off.

any suggestions on where to start looking to troubleshoot would be greatly appreciated.

thanks,

doug s.

Yes. It's most probably the voltage sensor.

These were made by Motoplat and are renowned for their unreliability. They work by sensing the voltage at the battery. When this goes below 12.35 volts, on comes the light. (This is why the bulb lights up when the engine is idling with the headlight on - the alternator is kicking out less juice than the headlight is pulling out of the battery).

BUT:

Before relaxing, do first check your regulator output.

Fire the beast up and stick a voltmeter across the battery terminals. Rev the engine up to around 3,000 rpm and you should see the voltage go up to around 14, 14.2 volts. If it does, all is dandy and you can ignore the idiot light (or replace the voltage sensor, if you must and if you can find one).

If the voltage doesn't go up, come back.

P.s And as a piece of general good house-keeping, pull the leads off the regulator and clean the terminals with a brass wire brush and some electrical cleaner - lemon juice, at a pinch. The terminals corrode over time and that leads to all sorts of unwanted problems.