M1009 lost all electrical power

[deercoker]

After driving my M1009 for about 10 miles it suddenly died and lost all power, fuses appear good and we tried to jump it but with ignition switch on there are no lights at all as if power is not getting to the switch or not leaving the switch, please any ideas as I am basically stuck roadside with no voltmeter

 

[sneekyeye]

check the fusible links at the firewall. I had the same thing happen to me and it was a blown fusible link shorted out by a can of soup. Pull on them, if they are blown they will stretch and come apart

 

[deercoker]

Have 22.7 volts at right hand terminal marked A, no voltage out of B, C or D, I know 22.7 is low and the front battery is bad but could this relay be bad?

 

[sneekyeye]

I doubt it, really. let me grab a photo of where to check. Also i believe my wiring is probably not correct for a truck that still has the glow plug resistor, mine was gone and its all 12v here.



Pull on these wires near the little black round plastic barrels in the middle. if they are bad they will stretch.
Your power to the glow plugs is going to be good then, but without the 12v to the rest of the truck, it wont be able to be turned on.

 

[Guyfang]

To test the relay, take all the wires off. Then apply 12 volts to B&C. it should click/clunk. Use an ohms meter on A&D, you should have continuity. Pin A is from the battery. Pin D is output. B&C are your two wire to turn it on, or cut it off.

 

[deercoker]

To test the relay, take all the wires off. Then apply 12 volts to B&C. it should click/clunk. Use an ohms meter on A&D, you should have continuity. Pin A is from the battery. Pin D is output. B&C are your two wire to turn it on, or cut it off.

Thanks I will check it in the morning

 

[dougco1]

Have 22.7 volts at right hand terminal marked A, no voltage out of B, C or D, I know 22.7 is low and the front battery is bad but could this relay be bad?

IMHO & IMPE
If your front battery is bad as you stated, you should paus all other repairs in till you replace it.
My M1009 acted the same way and it turned out to be a bad battery that had a few of the cells shorted.
Low voltage can and most likely will destroy your starter relay under the dash by welding the contacts shut. So also check your relay, or you may be in for a more expensive experience than you think.
Low voltage = stuck relay = runaway starter = burned up starter = burned up wiring = a lot of $$$

Just saying

 

[deercoker]

To test the relay, take all the wires off. Then apply 12 volts to B&C. it should click/clunk. Use an ohms meter on A&D, you should have continuity. Pin A is from the battery. Pin D is output. B&C are your two wire to turn it on, or cut it off.

No clicking or a clunk with 12 volts to B and C, also no continuity between A and D, also charged the front battery overnight and it tests good with a loadtester

 

[deercoker]

No clicking or a clunk with 12 volts to B and C, also no continuity between A and D, also charged the front battery overnight and it tests good with a loadtester

Next question is would a bad relay kill all power in the cab?

 

[Guyfang]

No clicking or a clunk with 12 volts to B and C, also no continuity between A and D, also charged the front battery overnight and it tests good with a loadtester

The relay says 12 volts. If you applied 12 volts to the B&C and nothing happened, then its bad.

 

[deercoker]

The relay says 12 volts. If you applied 12 volts to the B&C and nothing happened, then its bad.

Next question, where could I find one? Napa and the other parts stores have one with two terminals and a harness plug in, thanks

 

[sneekyeye]

I think you're chasing the wrong problem with the glow plug relay. If it were stuck open, it most likely wouldn't have blown anything. If it would have stuck shut, the glow plugs would have likely all burned up. If you are decent with a wiring diagram, you need to start measuring voltage at the positive bus bar and keep going on down the line until you find where there is no 12V. Whether it's nothing on the inside of the cab, or what. Without a meter or a power probe or test light, you're going to have a hard time of it.

 

[nyoffroad]

If you are still stuck on the road side, run a jumper wire from the positive terminal on the FRONT battery (12volts) over to the pink wire on the injection pump. Then after making sure the truck is in park (double check) and or maybe the transfer case in in neutral, use a screwdriver or other metal object to jump the starter. That would be from the large heavy cable going to the starter solenoid over to the small wire next to it, IIRC that small wire is purple. Truck should crank over and start . This will bypass the ignition switch/glow plugs and relay. Get it home then start trouble shooting.
OH yeah, to shut the truck off just unhook jumper wire at front battery. Good luck.

 

[deercoker]

If you are still stuck on the road side, run a jumper wire from the positive terminal on the FRONT battery (12volts) over to the pink wire on the injection pump. Then after making sure the truck is in park (double check) and or maybe the transfer case in in neutral, use a screwdriver or other metal object to jump the starter. That would be from the large heavy cable going to the starter solenoid over to the small wire next to it, IIRC that small wire is purple. Truck should crank over and start . This will bypass the ignition switch/glow plugs and relay. Get it home then start trouble shooting.
OH yeah, to shut the truck off just unhook jumper wire at front battery. Good luck.

Thanks I got it towed home now just troubleshooting, I appreciate the info

 

[deercoker]

Thanks I got it towed home now just troubleshooting, I appreciate the info

Update::: put a new glow plug relay in and a new front battery and she fired right up, thanks everyone for the replies

 

[Mullaney]

Update::: put a new glow plug relay in and a new front battery and she fired right up, thanks everyone for the replies

.
Congratulations!!
Glad to hear that you got it fixed...

.

 

[dougco1]

Update::: put a new glow plug relay in and a new front battery and she fired right up, thanks everyone for the replies

So the front battery must have ended up being bad?

 

[deercoker]

So the front battery must have ended up being bad?

Don't think it was according to my load tester, however I changed it out because it was smaller than the back so they were miss matched and the bracket was not sitting on it correctly, I will use it on my boat though, still puzzled how the glow plug relay could shut off the power to the ignition switch and engine

 

[sneekyeye]

Is the front battery being charged correctly?

 

[dougco1]

Don't think it was according to my load tester, however I changed it out because it was smaller than the back so they were miss matched and the bracket was not sitting on it correctly, I will use it on my boat though, still puzzled how the glow plug relay could shut off the power to the ignition switch and engine

I still think it was a bad battery.

My M1009 acted the same way as your ride and had me buffaloed for days. I went through all the motions of checking everything electrical. I even disconnected and cleaned all the grounds and fuse holders with no joy.
The battery and its connections was the first thing and then again last thing I checked. The clue finally came to me when the battery wouldn't charge above 12 volts nor hold the charge overnight. The next day it would read 10 volts.
I brought it to NAPA, their load tester said FUBAR when my el-cheepo home tester said it was good.
Hooked up the new "group 31 truck battery" they sold me and problem solved.

IMHO,
These CUCVs were well engineered back in their day but all their components must be "working together" as designed. If one part of the system is broken, bypassed, missing, or modified, it most likely will show up as a bigger issue down the line.