m939 series schematic

[rogersn67]

I have been looking for the actual schematic for the rear wiring harness on a m939 truck for about 2 days now. Maybe I am loosing my mind, but I can not seem to find it in the TM's. I thought this should be in the Organizational level TM, but there does not seem to be one for the M-939 series truck available. I have seen that TM for sale, but can not find it online. Does anyone know where to find the wiring schematic, or should I just buy the TM I saw and hope it has it in there?
Thaks in advance!

 

[emmado22]

I'd try the P2P program in the resources section here.

http://www.steelsoldiers.com/5-ton-up-tms/79228-tms-939-series-trucks.html

 

[rogersn67]

Ok, thank you.

WOW! I had no idea what that was before.

I will dig through this later!

 

[Artisan]

Well, if there is a schematic in a all that it would take a month of Sundays to find it.
My Low Air light was / is intermidetant. Reading the TM's I did a continunity test
of line 57 while at running pressure and got nada so I guess it is a good place to start,
finding the other end and doing a continunity test on the wire then look at what it is
connected to, of which a wiring schematic would probaly tell me...

 

[ARYankee]

Do you have the P2P program? It is a great tool to have for these trucks. Here is the link: http://www.steelsoldiers.com/showthread.php?82818-M939-P2P-Program-On-SS

 

[Artisan]

Here is a partical schematic I found.

The green arrows point at the two low air switches.
I tested them w/ the OHM meter on 200 and it read .3

The TM says if it is other than 300 ohms the air switches are bad.
I do not know if .3 = 300 or what...for alls I know I have 2 bad
low air warning switches too...

The magenta arrow points at line 57 but there is no schematic, it goes to a symbol
like a sideways letter "E" ???

 

[ARYankee]

That "E" is ground. When did you test those switches? I would ohm them out when the truck is running and at pressure, then I would check them when the truck doesn't have air. I'm assuming that they are normally closed switches and when the truck builds pressure it opens the switch which turns off the buzzer.

 

[ARYankee]

The P2P will really help you if you have a PC or laptop to install it on. You can download it here: https://docs.google.com/open?id=0B6t...TVmaHJLRVl6dU0

I just downloaded and installed it on my laptop. I have it installed on my PC at home. I just pulled up the Failsafe Warning Control Module. It has a written description and a good schematic. Those switches are wired in series.

 

[wheelspinner]

Full schematics are in Maintenance Manual, Part 4- Attachment "H".

 

[Artisan]

Money is tight right now, normally I would just throw new parts at something like this
since it is a safety device and parts are old'er' .

TM 23-1 had a troubleshoot and I did it and I "think" my issue is the
failsafe warning control module.


Sometimes the Low Air light comes on, and some times it does not.
Intermitent in functionality it is. I guess i will look for a box and throw
that at it first.

The P2P was a good help.

I much appreciate the input.

 

[Artisan]

Wheel thanx for the input but I do not understand.

Do you mean in TM-9-2320-272-23-2 Chapter 4?

 

[wheelspinner]

Wheel thanx for the input but I do not understand.

Do you mean in TM-9-2320-272-23-2 Chapter 4?

No when I downloaded them them the maint manual is in four parts. Its the fourth part in the appendixes after chapter 6.

I hope that makes sense.

 

[Mike929]

The P2P will really help you if you have a PC or laptop to install it on. You can download it here: https://docs.google.com/open?id=0B6t...TVmaHJLRVl6dU0

I just downloaded and installed it on my laptop. I have it installed on my PC at home. I just pulled up the Failsafe Warning Control Module. It has a written description and a good schematic. Those switches are wired in series.

Do you have to have MS Access to run it? When I try to install it comes up with a pop up saying I need to buy additional MS products to run it. I have word, excel, PP, but no Access.