M925a1 wiring diagram

[Artisan]

Is there a wiring diagram I can "try" to deciper available anywhere.
Looks like I have to replace wire 57.

 

[porkysplace]

Try the link in post #2 m939 series schematic

 

[wheelspinner]

Maintenance manual Part 4, Appendix "H"

 

[Barfkiller]

Try the "foldout_figures" in TM 9-2320-272-23-5. They are toward the back of the manual.

 

[Artisan]

Try the "foldout_figures" in TM 9-2320-272-23-5. They are toward the back of the manual.

There it is, page 611 THANK U Barfkiller!

 

[Barfkiller]

From what I can see on "FO-2. M939/A1 Electrical system wiring diagram (2 of 2)" in TM 9-2320-272-23-5, wire number 57 is listed in two different spots. Both are ground wires, one for the air pressure switch.

My truck had issues with the low air buzzer not turning off even with the guage reading 120 psi. Drove me crazy because it would not happen every time I started it. When it would not shut off, I would crawl under and tap the air pressure switch. Took me a while to figure out which one it was. It would shut off after I hit it. I guess the proper term would be smack the $*%# out of it. I am planning a replacement when the weather warms up. It has not been acting up as of late, maybe a good beating is all it needed.

 

[Artisan]

My low air warning is not turning ON regularly.
It seems to have a mind of its' own. I can
only start throwing parts at it when I can.

Sometimes the low air light comes on, other times it does not.
This is bad, I want to fix it .

 

[Barfkiller]

If you are going to replace the air pressure switches anyway........I would "tap" on 'em a few times with something heavy.

 

[Artisan]

If you are going to replace the air pressure switches anyway........I would "tap" on 'em a few times with something heavy.

I took one out, rapped it against my desk trying to extract crap.
I guess I should just throw parts at it to be safe.

I know for a fact my truck "sat" for a long time.
When I pulled the fuel filter you can see a DEFINATE
line of rust inside it where water rausted the housing.

little by little I will get er done ...as permits .

 

[juanprado]

try the troubleshooting flow chart for the failsafe warning buzzer box. The air pressure switches, light , buzzer all go through this gizmo. it is in tm 9-2320-272-23-1