1985 CUCV M1008 #2 GEN. Light

[kenny]

Thanks for the help!!
It is fixed.
It was eather a loose wire on the + block on the fire wall.
or the 3000 pounds of pecan shells I put in the bed yesterday.
But it all good now!!
It sure is nice to have so many people here helping me out.

Thank You!!

 

[Armada]

Update: Took #1 gen in for a test and rebuild, it was shot, no output. Had it totally rebuilt. Brought in #2 and it still had output but had it rebuilt anyways. They were both the original gens and had never been opened up. There was 74K mi. on them. They are much quieter when running now and everything works fine again.

 

[rockspider]

Armada when a light remain dull even when driving, it could means that one of the three diodes is dead in the circuit board inside the alternator (needs servicing).
As far the grounds, only one alt is grounded, the first one which is producing 12v between ground (ZERO) and +12.
The second alt. is isolated because it has its minus lug connected to +12v, so it see +12v as the zero, and the 12v it produces then are from +12v to +24v.

Pfew, not easy explanation in a foreign language for me! LOL!

 

[n1vbn]

OK CUCV 101 electrical systems.

Item number one .....number two generator light won't come on when the key is on engine not running. Kiss priciple applies here guys. Replace the light bulb in the dash. Turn key on....Light lights up? Start engine wack throtle to kick both alternators in and check voltage om dash meter . Everything being right should be at or above the 28 volt notch on the meter. The Army specified that Chevy build em WITHOUT the resistor that normally connects both terminals on the idiot light. The normally install on civvy vehicles that allows civvy vehicles to continue to charge after the light burns out. The Army wants the Soldier to take the vehicle to the motor pool for repair instead of ignoring it. When the light burns out no power gets to the field connection of the voltage regulator hence no power is generated. A real generator uses real magnets that create electricity when the commutator is rotated...an alternator requires an external electrical power source to create a magnetic field so the alternator can create electricity. as soon as the alternator spins up using the electromagnetic field to create power as soon as the voltage matches the power coming into the voltage regulator it putts the idiot light out because it has now become "selfexciting" it no longer requires external power to generate power.




I know ...a little long winded reply but the only way I know is to explain it completely.

 

[mangus580]

James, also keep in mind, there is some relay used for the Gen2 light as well. It might be possible that this relay has failed.

Now you got me thinking of making a vehicle Troubleshooting Section. that would allow us to hate little write-ups about things like this in an easy to find format.

Sound like a good idea?

 

[SouthernSteel]

Im all for that as im going thru my own ordeal THe electrical is the most fun for sure