More charging whoas

[carter262]

More charging woes

So I have been fighting this for some time. been through re manufactured alternators, rebuilt alternators, new batteries, new bulbs, new wires, and so on.

So it appears that the 24 volt battery, rear battery, is not getting charged properly. So just like everyone else I'm looking for advise.

Here are the symptoms:
Gen #2 light. no glow
Volt gauge: in the green but barely
Will start when batteries have a fresh charge from a battery charger. eventually though will not start, due to not enough juice. When batteries are checked later the rear one is always the low one.



Here is what I have done thus far,
Replaced both batteries, battery cables, and alternators. The alternators have been replaced at least twice.
I replaced the GEN #2 bulb today with a new 194 bulb. Still no glow. Tried a different new 194 bulb. No glow.
Checked the printed circuit board, no breaks or burned places.
Checked the wiring that feeds the printed circuit board for Gen #2 light. NO volts with key on or off. Gen # 1 light shows 12 something with the key on.
I have checked the voltage at the back of both alternators and they were 14 something.
All fuses in the fuse box are good and have been replaced with new ones.

So I know that is the GEN #2 light is out or not the correct bulb then it will cause charging issues. So could the issue be one of the fusible links. This is where I am leaning. Based on the diagrams and reading it looks like I need to replace these three (info from fusible link sticky):
Diagram E-9 – .5 ORN-2K - 24v POS Term BD - 24v to GEN2 exciter circuit - 20ga
Diagram E-9 - 3 BLU-2L - 24v POS Term BD - 24v to GEN2 positive terminal - 12ga
Diagram E-9 - 3 BLU-2H - 12v ENG WRG Harness Block - 12v feed to GEN2 negative terminal - 12ga - This is where the "Isolated Ground" comes into play
Are there others that I need to be worried about?
Am I looking in the wrong place?
Could it be something else?

 

[PeeWeeQ]

I'm having the same woes...

Ive rebuilt both gens, replaced ALL fusible links, cleaned connections and grounds, new batteries and still no gen 2 light. I've been through the bulbs, but tonight I'm going to replace bulb sockets, check the PCB more closely, AND check the gen 2 diode...

Hang in there, we'll get it!

 

[GunnyM1009]

If you have a multi meter check both sides of the 10amp fuse in the bottom of the fuse block. If you have 24v at both sides move to the bulb and socket pull the bulb and check voltage at bulb socket if you have no voltage there then it is likely your pcb or contacts. Lightly clean the pcb contact points with a pencil eraser. Then lightly bend the bulb socket contacts out a little and lightly go over them with a fingernail file. Then put the socket back in and check voltages.

 

[GunnyM1009]

Also follow the the circuit on the pcb and check voltage at the pin on the connector for the gen2 light. You will more than likely have voltage there if you have it at the 10amp fuse. If you have voltage at the pin but none at the socket and cleaning the contacts does not help you may have to get a new pcb.

 

[Westech]

good advise on the cleaning Gunny. I have found that to be a issue many times with the Gen lights and all the other lights on the back of the dash.
30 years of oxidation will do that.

 

[carter262]

Also follow the the circuit on the pcb and check voltage at the pin on the connector for the gen2 light. You will more than likely have voltage there if you have it at the 10amp fuse. If you have voltage at the pin but none at the socket and cleaning the contacts does not help you may have to get a new pcb.

OK i will check the voltage at the 10amp fuse you mentioned, but I have already checked everything at the pcb. there is no voltage coming into it at the Orange and black wires, #6 & #7, on the wire plug that feeds power to the pcb. so that is were I am at and trying to figure out. I will admit though I should of checked the voltage today at the 10 amp fuse but forgot to.

Thanks for the help

 

[GunnyM1009]

good advise on the cleaning Gunny. I have found that to be a issue many times with the Gen lights and all the other lights on the back of the dash.
30 years of oxidation will do that.

Yeah I just had to go through this whole process for both Gens. I had to have a new pcb and 2 fusible links.

 

[GunnyM1009]

OK i will check the voltage at the 10amp fuse you mentioned, but I have already checked everything at the pcb. there is no voltage coming into it at the Orange and black wires, #6 & #7, on the wire plug that feeds power to the pcb. so that is were I am at and trying to figure out. I will admit though I should of checked the voltage today at the 10 amp fuse but forgot to.

Thanks for the help

If you have no voltage at the 10 amp fuse then tracing backwards I think your next step would be fusible links. Someone correct me if I am wrong I think that is the next step in the circuit though.

 

[Warthog]

The 10 amp fuse controls the GEN2 relay that feeds the 24v to the alternator.

Read the GEN2 sticky. I documented the voltage flow thru the GEN1 and GEN2 circuits and all the various things to check.

 

[carter262]

The 10 amp fuse controls the GEN2 relay that feeds the 24v to the alternator.

Read the GEN2 sticky. I documented the voltage flow thru the GEN1 and GEN2 circuits and all the various things to check.

10-4, I'll go back and look. I must of missed the Gen#2 sticky

 

[Warthog]

The sticky was there but I just changed/corrected the title.

 

[the skull]

Check the fusible link for Gen 2 that comes off the diamond shaped junction block.
Mine looked good, but pulled apart when I touched it.

 

[Tinstar]

Don't forget to also check the gen2 relay under dash.
There is also the gen2 diode, but not sure if that will cause any issues.

 

[carter262]

Don't forget to also check the gen2 relay under dash.
There is also the gen2 diode, but not sure if that will cause any issues.

Had a minute to check a few tings today.
There is power at the 10 amp fuse. As posted before there was no power on the wires feeding the pcb.
Started to change out the fusible links but NAPA was out of the 12 gauge so I had to order it which stopped me from changing out the Fusible links today.

Can you describe or even better provide a picture of the gen 2 diode and where it is.
Also if the gen2 relay is out would it cause the wires that supply the gen2 light on the pcb to not have power?

 

[Hasdrubal]

Here you go..

 

[GunnyM1009]

http://www.steelsoldiers.com/showthread.php?121589-CUCV-GEN1-and-GEN2-Exciter-troubleshooting. Go to this link and scroll down to gen2 it explains each step in the circuit.