1985 CUCV M1008 #2 GEN. Light

While changing the dash pad yesterday my volt gen meter arcked on the metal part the dash pad mounts to and stoped working.
I replaced the 20 amp 28 volt fuse in the fuse block and it works now and apears to be charging while running.
Now the # 2 gen light does not come on with the #1when the key is turned in the run position like it use to do.
I have checked the fuse links on both alt. and the ones on the glow plug relay and the 4 on the + block on the fire wall as well.
all seem to be good and the #2 gen light bulb is good also.
All I can find is that I am not getting power to the bulb.

Could some one please tell me what else I should check.

Thanks Kenny

Trace the wire going and comming from the bulb. See where it goes, I forgot who, but someone has a manual on CD here...Give it a few more days for folks to answer this post.

The manual is posted here on the site. Look in the TM section, and you will find it.

Thanks Ncinirator and Mangus580 for the info.
I will try to find it in the TM section

Which is the #2 side? The left side gen light on my 1009 has a dull glow to it. They are both on when I start it, but after a tap on the throttle, the right side goes out, and the left goes to a low glow. What could be the cause? Belt, ground, nothing to worry about?

When you are sitting in the drivers seat, looking at the lights, the Alternators are on the corresonding side. Gen 1 is drivers side, Gen 2 is passenger.

I would suspect that your Gen 2 has something wrong. I would pull it off and have it checked out before it fails totally

(belt and ground could be the cause too)

I see every thing for a light on but nothing for one off.
O Well maby someone here has had this happen to them before and just has not seen the post yet.
This was the same light that use to flash on and off while driveing down the road,Turned the head light on or the blower on high and it stoped flashing.
I guess I should not never wished for it to stop flashing because it does not evin come on any more.LOL!!

Get out the ohmmeter and start tracing. On a related note, I had one of my 1009 alternators rebuilt, New bearings, regulator and rectifyer. Is $100 about right?

Yup. Keep in mind, that the alternator in the CUCV is basically a civvy alternator. The parts are interchangable. so dont let someone pull a fast one on you.

Kenny, did you check the printed circuit 'board' in the back of the instrument panel that the light connects with for any breaks/shorts? Is the bulb holder making a good connection to that? I've seen those get pretty corroded.

I pulled out the bulb holder and looked at it but i did not look at the circuit board.
What I do not under stand is that if you can jump start one of these trucks by conecting to the front battery,Why won't one alt. charge both sence they are conected together.
Well I am off to try the Ohmmeter and if they are both working I guess I will pull the dash apart again and check the circuit board.
Thanks again for all the help.

Ummm... hang on a second here. You cant jump one of these trucks by using the front battery only. Wont happen. the starter is 24v, and the front battery is 12v. There is a chance, that depending on why it needs a jump, that it will work, for example if you left hte lights on, the front battery (12v system) would be dead, and in this case, it would work. But if both batts were dead, you would need to jump 24v instead!!!!

Did you actually verify the bulb was good using it elsewhere?

I would suspect that your Gen 2 has something wrong.

Click to expand...

Mike, you mean a problem with my gen 1 (left/drivers side), since it's my left light that is on. I pulled the gen 1 today and will take it in for a check tomorrow. What should the outputs be on these generators? Are they both the same?

Yes sorry.... missed that part...

and yes, they are both the same. when you take it in for a check.... make sure they ground it using the ground stud on the back of the case. (that is the only diff between these and civvy ones) The output should be typical of any GM alternator.

They are 100 amp alternators right? Thats what the two on my old 1008 were.

yes they are, just be sure tha if you need it rebuilt that they keep the isolated ground, otherwise you will have about 8 fusible links to replace under the hood and the problem of finding a new set of resisters for the glow plugs. Thats what happened to me. the #$@#@ manager didn't want to even cover the cost of fixing there screw-up until I talked to the owner, and he got written up and I got a certificate for TWO FREE REBUILDS!!!

I hate it when that happens.... If you have it rebuilt, check for the isolated ground before you put it back in the truck. (well, before you hook all the wires up at least)

thanks for the help troubleshooting it, all of my issues have been electrical related except for the warped rotor that ate two sets of wheel bearings before I figured out the cause.

What/where is the isolated ground?

it just means that the guts are not grounded to the alternator outer housing, instead they are grounded to a lug on the back of the alt.