M925A2 Electrical Short/Nightmare

[YBC Offroad]

Hey guys and gals, I am new to this forum and I'm sorry if I'm doing this wrong but I need some help with my truck as it has been a lawn ornament due to this issue. Has anyone had electrical short issues with these trucks? The horn never worked and the assembly in the steering wheel was non existent until one day the horn was blaring randomly while my brother was driving it and smoke came out from under the dash. All gauges except for the rpm and Speedo are dead. One gauge is clouded with black on the lense. Then my brother proceded to drive it again. (Everything still ran and worked besides gauges). Then the truck shut off on him and got towed home. Truck had plenty of fuel. Now the truck starts but shuts off within 5 seconds or so via the fuel shutoff actuator thing on driver side of engine. To get it to move in our yard, my dad took this actuator out and used the emergency shutoff. Where should i start to look for where something went wrong? Thanks everyone, hope I can get this figured out.

 

[NDT]

Sounds like the common 60 amp alternator runaway voltage failure. Burns up the gauges. See what your system voltage is engine running and off and report back.

 

[YBC Offroad]

I will go check when I get the chance. What would be the extent of the damage?

 

[74M35A2]

First place to consider is the PCB, since it provides power to the dash. Tach and speedo work because they are mechanical.

 

[YBC Offroad]

Where/what is pcb? And I'm getting 0 volts out of the alternator???? Is this plausible?

 

[74M35A2]

It is a dual solenoid power relay box. One controls starter signal, and the other controls dash power. Replace the PCB, alternator, and make sure you are shutting the truck down in the correct switch order if you continue to use a stock alternator.

 

[doghead]

How can one learn the correct shut-off order?

Does this shut-off order help keep you from damaging the electrical system?

Where is this secret info found?

 

[73m819]

How can one learn the correct shut-off order?

Does this shut-off order help keep you from damaging the electrical system?

Where is this secret info found?

?, sorry I am not authorized to answer that question because I may get a nasty note from the admen. (a infraction) if the KGR slips which has happened BEFORE.

 

[YBC Offroad]

So where is this pcb and is it possible that the alternator is putting out 0 volts?

 

[porkysplace]

How can one learn the correct shut-off order?

Does this shut-off order help keep you from damaging the electrical system?

Where is this secret info found?

I heard there is a viscous rumor that they actually have a TM (-10) with that information , I also heard a rumor that no 2 snowflakes are alike.


https://www.youtube.com/watch?v=r10cufRqeDU

 

[frank8003]

I am just sitting back watching this one......

should I help
Hold hands and pray?

NAAHHGHH, get a beer and watch.

I searched Google everywhere on my phone for a -10 and
all I get is undersized under ware ads!

Now you did it, What is a -10?
What is "report back?"

Or......... go read some more.
https://www.doityourself.com/stry/how-to-find-an-electrical-short

https://www.steelsoldiers.com/showthread.php?85317-M925A2-Delco-Style-Alternator

 

[YBC Offroad]

So why do you think i didn't try all this before? I'm just asking a simple question which none of your links do anything to help.

 

[porkysplace]

So why do you think i didn't try all this before? I'm just asking a simple question which none of your links do anything to help.

TM9-2320-272-24-1.pdf
TM9-2320-272-24-1 Unit, Direct and General support manual for the M939 series truck. 1 of 4. Oct. 1992
Section VI

M939_P2P.zip
M939 Series Interactive Systems Guide - Download .zip file, right-click the .zip file and select unzip contents, put the M939 P2P file in your Program Files directory, open the M939 P2P folder, right-click on the runa6w32.exe file, select Send To, select Desktop (create shortcut), go to desktop, right-click on the new shortcut, select properties, select the shortcut tab, make sure the target box shows "C:\Program Files\M939 P2P\runa6w32.exe" c:\Program Files\M939 P2P\nav.a6r, make sure the start in box is empty. This should allow you to double-click the shortcut on your desktop and start the P2P program.

 

[74M35A2]

Did answer. Study the PCB diagram.

Where are you in your diagnostics? With the P2P wiring diagram program and a meter, you should be able to resolve it.

 

[porkysplace]

Hey guys and gals, I am new to this forum and I'm sorry if I'm doing this wrong but I need some help with my truck as it has been a lawn ornament due to this issue. Has anyone had electrical short issues with these trucks? The horn never worked and the assembly in the steering wheel was non existent until one day the horn was blaring randomly while my brother was driving it and smoke came out from under the dash. All gauges except for the rpm and Speedo are dead. One gauge is clouded with black on the lense. Then my brother proceded to drive it again. (Everything still ran and worked besides gauges). Then the truck shut off on him and got towed home. Truck had plenty of fuel. Now the truck starts but shuts off within 5 seconds or so via the fuel shutoff actuator thing on driver side of engine. To get it to move in our yard, my dad took this actuator out and used the emergency shutoff. Where should i start to look for where something went wrong? Thanks everyone, hope I can get this figured out.

I don't know if being a member for 3 year qualifies you as "new to the forum" , it was suggested in your other thread from 3 years ago to download the TM's , it looks like you didn't .

So you ever get your winch working , you never updated your thread from 3 years ago.

Winch problems

Started by YBC Offroad, 03-07-2015 20:49

 

[YBC Offroad]

I haven't been active since then as i got the winch working. The TM didn't do anything to help me in that case. I don't get why everyone is so hostile on this forum. I don't know anything about these trucks or the terminology you guys are using but instead of explaining everyone decides to be d bags about it.

 

[162tcat]

I haven't been active since then as i got the winch working. The TM didn't do anything to help me in that case. I don't get why everyone is so hostile on this forum. I don't know anything about these trucks or the terminology you guys are using but instead of explaining everyone decides to be d bags about it.

Read the -10 tm at least. Then do some searching on the site with the terms these guys have used.
I'll leave it at that or I might offend someone. Don't need another angry wife coming on here....


Sent from my iPhone using Tapatalk

 

[porkysplace]

I haven't been active since then as i got the winch working. The TM didn't do anything to help me in that case. I don't get why everyone is so hostile on this forum. I don't know anything about these trucks or the terminology you guys are using but instead of explaining everyone decides to be d bags about it.

Well if you would read the TM's you would know the terminology we are using , it's pretty hard to help somebody who isn't willing to learn or put a effort in understand what people trying to help you are saying. Instead of trying to learn something about your truck you come back calling people d bags because you didn't get spoonfed a instant answer . I'm sure if you look in the yellow pages you can find a mobile truck mechanic you can call names.

 

[YBC Offroad]

I read the manual like you said. If I'm still asking a question it's probably cause the manual was no help. Sorry i didn't see the term that was listed one time in the 1000 pages. I'm willing to learn why would i be here if i wasn't. The manual shows an external voltage regulator when that isn't the case! So now I'm lost which is why i am asking more questions. I don't understand the hostility here. I'm just trying to learn and diagnose the issue. So please either help me and point me where to go next or just stop trolling.

 

[74M35A2]

Replace both solenoids in the PCB and update the alternator with a Chinese Delco clone. From there, if any gauges are not working, replace them one-by-one. Your ABS module may be wiped out also. Same with CTIS module. Replace both of those if you want them functional again. Make sure your batteries are less than 5 years old, put your fuel cut solenoid back on, and everything should be functional, as long as nobody jacked with any of the wiring, or none of it has been damaged from too many amps.

From the member side of this, people take time to document things to help others. If somebody is asking a question that an answer is already readily available, then it can get frustrating. If a member just selfishly wants and does not contribute back, that can be equally frustrating. We don’t know what you read or checked to begin with, so we don’t know where to chime in. I’m just a pawn here, but the perception of this forum outside of this forum is not really understood. We’ll help those that first try themselves. It’s that easy. Name calling is actually prohibitied and warrant for expulsion. It definently won’t get your truck fixed.