Needed assistance, New M920 owner Ele problem.

[USA642]

Just bought an M920, picked it up yesterday, and was on my way home.
I stopped to fuel up, when I got on the interstate, I turned the fan knob from lo to med and the truck died.
Pulled over and tried to start it again but when I turn the key, NOTHING happens, push the start button and nothing.
$750 to have it towed from the interstate to a parking lot 5 miles away.

 

[NDT]

Ouch. Get a multimeter and trace the 12 volt feed from the batteries back to the ignition switch. The ignition switch is a weak point for that truck.

 

[AZK9]

... $750 to have it towed from the interstate to a parking lot 5 miles away.

Sheeeeesh! That seems excessive! Did they tell you what it would have cost to take it all the way home?

 

[wreckerman893]

The older M915/M916/M920's all had electrical gremlins.

I sat on the side of the road until daylight on a recovery trip because the headlight switch went teats up.

Parts are available through NAPA.

If you open the dash panel and look for the big solenoid you can sometimes jump across the terminals with a screwdriver and the truck will start.

 

[USA642]

Ouch. Get a multimeter and trace the 12 volt feed from the batteries back to the ignition switch. The ignition switch is a weak point for that truck.

You are/were absolutely correct.
Checked the batteries individually, then checked all my fuses and relays.
I looked at the ignition switch and it has 7 wires going to it.
2 blue ones on top, a yellow one on the bottom and 4 in the middle.
The 4 in the middle are together in a plug.
The red one (on the right) overheated at some point (long before I got it) to where the prong on the switch is rusted.
Cut the right wire off, put a female spade connector on it and the truck started right away.
Do you know if there is an aftermarket switch to replace the one in the truck?

 

[USA642]

Thank you for your helpn NDT

 

[USA642]

Hahaha, no, I didn't dare ask!

 

[USA642]

Wreckerman893, I tried that but my automatic transmission didn't light up, so I continued until I found the problem.
Thank you for your suggestion.
I will check with NAPA as soon as I get home.

 

[NDT]

Great news. Yes there is an aftermarket replacement for the switch, take if off and bring it to NAPA or similar. If they can't cross it, there is a thread here with the part number that will take some searching to find.
Next thing that will leave you stranded is the alternator, with the 7155 close behind. Take some time to read some of the threads here, search "M915" or "M920". Once you become familiar with the quirks, the trucks can be fixed on the side of the road, and hopefully no more heavy wrecker bills.

 

[USA642]

AZK9, EVERYTHING was excessive in that **** town (Vermillion, SD)

Tow bill $700 + $42.xx TAX
Hotel room $161 + fees and taxes
Mechanic $175/hr ($500)

Will avoid that town at all cost from now on, everyone is extremely proud of their stuff/services...

 

[USA642]

Thank you NDT, that was my first thought when I chose to buy the truck, everything should be SIMPLE, since you don't want a military vehicle breaking down in the field and being unable to be fixed right there...
It's my first time on the site so I might need some help learning to find stuff like "threads"
Really appreciate all your comments and help.
By the way, what's "the 7155"?

 

[quickfarms]

The 7155 is a cat transmission. Some people love them, some hate them. If you love them that has a habit of ending if you ever have to work on it or find somebody to work on it.

 

[Artisan]

I believe that switch to be a POLLACK 31-164

The pic in the PDF at the top shows something different, look lower.

Glad your up and running, NDT is awesome.

The " Artisan's M916 " thread has all your TM's on page 1, you
should DL them all and put them on a tablet / ipad and keep it
in the truck. I have all TM's in print as well. You will want them.

DO NOT RUN YOUR HEADLIGHTS WITH THE DASH LIGHTS DIMMED.
Keep them at full bright. That switch heats up BIG TIME and can
burn / smoke. Another known flaw. You need to open the panel
that houses the headlight switch and give all those wires in
there a real good visual. The headlight switch is the same
as a 79 Jeep truck "I believe" .

MAKE SURE YOU GET FRONT AND REAR CLUTCHES ON THE TRANNY
ENGAGED AS QUICK AS POSSIBLE. That tranny is REAL EASY
to destroy. Normal flat road driving, If bobtail, start in maybe 7, then go to 9 then to 11, after
that you can only go 1 at a time up using the ratio selector (shifter) .

The 5th wheel pin is 3.5" .

The starter and trailer lights are 24V, very little else is 24V, lots
of 12V everywhere else. Test the cigar lighter to see if you have 12
or 24V's there too.

Perhaps change door locks and ignition tumbler, so others do not have access.

The M920 is part of the M915 SERIES of trucks.

M915
M916
M917
M918
M919
M920

 

[dmetalmiki]

Wow..They sound a really straight forward un complicated and simple to run military vehicle. I just can not believe they turn things like that out for military use.

 

[ev2bfree]

Just bought an M920, picked it up yesterday, and was on my way home.
I stopped to fuel up, when I got on the interstate, I turned the fan knob from lo to med and the truck died.
Pulled over and tried to start it again but when I turn the key, NOTHING happens, push the start button and nothing.
$750 to have it towed from the interstate to a parking lot 5 miles away.

I just picked up my M916 and had the same experience. It ended up being the regulator was shot. I assume that at some point it was started and run with low, dead, or shorted batteries and took out the regulator. When I picked up the truck they had fresh batteries, which I thought was a blessing, but it just disguised the fact that the regulator was not functioning until I got down the road. Interesting you mention the fan was the death nail. It was for me to. there are many other M915, M916, M920 owner who have had similar experiences.

 

[simp5782]

Yeah. Middle of no where. I used to always gas up at that BP on the west side of the exit on my trips from Montana to Memphis. You should really get ahold of P3 Recovery that is in Western ND that has some videos on youtube. He has an HET incase you have issues in the future he is nearby with a bigger truck!

 

[Karl kostman]

USA642 WELCOME to the mighty M920 club, there are not to many of us and sounds like your and I are the only two in ND that I know of! Congrats on your purchase they are really great trucks but with that said they have their little things about them that it seems most others dont have. The 7155 is an extremely heavy duty trans and state of the art for its day, but it can be a little finicky at times! If you ever have questions on this beast feel free to PM me any time and I will sure do what I can to lend a hand!
Karl Kostman
Eastern ND