Search results

Here is another thread that covers solving air pressure building problems. It's a long read but contains some good info... http://www.steelsoldiers.com/showthread.php?141771-Air-Fails-To-Build-Intermittently-Parking-Brake

I had trouble this summer with building air and had to replace my air dryer and use 400grit sandpaper to clean sticky residue from the air compressor unloader valve to solve the problem. The story and details can be found here...

During normal operation a seperate device on the engine side of the firewall called the air governor signals the air dryer to blow off and the compressor unloader valve to stop supplying air pressure to the air dryer at a set pressure of around 120psi. There is a safety valve in the air system...

Perhaps a newer CTIS module that has communications capability could be used in place of the original?

Our M931A1 08/2010 RRAD rebuild NHC250 has 03/10 on the engine tag.

When the brake predal is pressed air pressure causes the brake light switch contacts to close and supply ground to the brake light circuit. I would guess an internal spring opens the contacts when the pressure diminishes. The brake light switch has two wires and is inside the drivers side frame...

I don't have much brake system experience but will try to get the ball rolling... When the brake pedal is pressed air pressure in the service brake system closes the contacts in the stoplight switch which lights up the brake lights. It sounds like at 70PSI something other than pressing the...

No problem, I knew you could get through it...hoping you or someone else may help me when I need it. Wire 35 and the sensor are up on top of the motor I believe. Perhaps someone who has actually laid eyes/hands on it can confirm. I would guess they deleted this alarm because it was prone to...

Regarding the alarm, there are two temp sensors. One sensor is for the temp guage that you grounded causing it to jump. This sensor has nothing to do with the alarm. The other temp sensor, or grounded wire 36/PIN D if the sensor has been eliminated, is what generates the temp alarm if open...

I rode in the back of an unloaded cargo (M924?) off road a few months ago and I would say they both are equally rough. My M931 has an added bed & bucket seats in the back which is way better than the troop benches. After a few minutes of the benches I learned standing is the better option.

If there's a decent amount of tongue weight it does.

I'm no CTIS expert but know a fair amount about digital electronics. I would assume circuits from the early 1990's or before would be ROM or EPROM(microchip lingo) based. If so the ROM could be not be altered and the EPROM would require a special programming device.

16K is really going to smooth out the ride, they're rough riding empty.

Welcome aboard, You may find these interesting if you have not already seen them... http://www.steelsoldiers.com/showthread.php?121487-TMs-for-M939-Series-Trucks

I would guess a signal problem from the wheel sensor(s) may cause a fault. Manuals are here... http://www.steelsoldiers.com/showthread.php?121487-TMs-for-M939-Series-Trucks

Can't verify accuracy but I read the military put a low speed limit (41mph?) on the early M939s until they were upgraded with the ABS system. Bear in mind over braking is not something you want to do especially with no load meaning less traction.

1. This post needs pics! 2. Not sure what the current draw is on your brake system, you can get something like this in the 20amp range... http://www.amazon.com/HOSSEN®-Converter-Regulator-Step-Down/dp/B00BWKXTUU/ref=sr_1_1?ie=UTF8&qid=1448239949&sr=8-1&keywords=24+to+12+volt+converter

I agree, the m939s are rated for 5tons mil. spec. Depending on how much you are hauling you may not need active brakes on the trailer. I have hauled over 3 tons with no trailer brakes and no issues. Tongue weight helps with traction so I have heard, never had any traction issues myself. I can...

Start with page 853 (WP 0099) in the following manual... http://www.steelsoldiers.com/attachment.php?attachmentid=462280&d=1384399085

Are you referring to the flasher unit on the drivers side interior firewall?