Check your ABS sensors for one. They might have some grime in them messing something up. Other than that, I'm sure a more experienced member will chime in shortly
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1986 M1009 CUCV
CUCV was assigned from1986->2005 with Beachmaster Unit 1 at USNAB Coronado
Most of the time they are broken off or just loose at the hubs I know sometimes if the truck has crossed thru deep water the abs light will come on truthfully ABS is just a pain in the rear end
All depends how well its hiden. Just look behind your tire and see if you can see a wire going to the hub. It not working isn't really a huge issue on a truck like this just have to be a little more careful with your breaking
Keep us updated on what you find. Since this trucks are coming out in mass we need to get a good database down in the forum for fixing such issues. My 932A1 has had a few unique issues that took a few days to trouble shoot.
The TM's for the 9 series trucks are not the best. I had a forum member help me on the phone to finally fix my air
brake issue !
There is a sticky in the 5 ton listing from Chris about the differences in your truck with and without abs, I personally wouldn't run the truck without it, the problem being it stops too well, causes fishtailing on pavement and is the cause of many deaths.
The Following User Says Thank You to jtron79 For This Useful Post:
DISTRIBUTION PROBLEM USER ACTIONS TACOM/PM ACTIONS SUPPLY STATUS POINTS OF CONTACT LAR INFORMATION 1. DISTRIBUTION: {Menu} A. MACOM Commanders will retransmit this message to all subordinate Commands/Activities within 24 hours of receipt of this message and acknowledge receipt of this message within five working days to: CDRTACOM, Warren MI, AMSTA-LC-LPIM, DSN 786-6096, Commercial (586) 574-6096 or DDN address: safetyofuse@tacom.army.mil. B. MACOM Commanders will also track and report compliance of this message for all subordinate Commands/Activities to: Mr. Terry Callahan, M939 Quality representative, AMSRD-TAR-E/TACT (586) 574-8450 or DSN 786-8450 email terry.callahan1@us.army.mil NLT 30 days from receipt of this message. 2. PROBLEM : {Menu} A. Reports from operators of M939 series vehicles equipped with anti-lock brakes (ABS) have stated that they are not sure of the meaning of an illuminated ABS amber light on the dash panel. Some operators believe that when the light comes on the system is operating properly, while others admit that they are not quite sure what it means. Drivers must be made aware that a steady illuminated ABS dash light indicates the vehicles anti-lock braking system is malfunctioning. Currently, the ABS dash light is marked only with a tag labeled "ABS" and gives no further explanation of the meaning of an illuminated lamp. B. Normally, upon start, the ABS light will illuminate for three (3) seconds and then go out. This is a normal ABS self test. These procedures are described in the PMCS section of TM 9-2320-272-10 Pg. 2- 44. If the amber light comes on and stays on, a malfunction exists, the maximum speed limit is reduced to 40 MPH. (Table 1-9A Operators Manual) Different braking techniques are required driving without ABS. See paragraph 3B and 3C below. 3. USER ACTIONS: {Menu} A. Driving with ABS functioning: (ABS light off) A fully functional ABS system allows the wheels to intermittently roll while drivers use full brake pressure. This rolling action allows the driver to regain traction control and stability on the rear wheels. B. Driving with ABS malfunctioning: (ABS light on) Drivers need to be aware that air brakes are very sensitive when trucks are lightly loaded, empty or when driving on wet/slippery pavement. This is especially evident when the ABS light is illuminated. The brakes must be applied gradually to avoid locking up the wheels. Although a steadily illuminated ABS amber light does not deadline the vehicle, it does render it Not Fully Mission Capable(NFMC). The M939's must revert back to the 40 MPH maximum speed limit imposed by Safety of Use Message 98-07. C. Complete driving instructions for M939's series vehicle with or without ABS, are found in the operators manual TM 9-2320-272- 10 C-2. (Starts on Pg. 2-156.2) D. Maintenance personnel must prioritize restoring any vehicle's malfunctioning ABS system. The Haldex Diagnostic Info Center is available using NSN 5895-01-515-9443 and should be used to record malfunction fault codes to make accurate maintenance diagnoses. The ABS fault codes are stored in ABS Electronic Control Unit (ECU) and can be retrieved using the Haldex Diagnostic Infocentre. This diagnostic tester plugs in under the passenger side of the cab. Troubleshooting should be accomplished as soon as mission and time allow. E. Although the current TM 9-2320-272-24 does not carry ABS Technical information, more detailed information has been available in TB 43-001- 62-01-1 (April 2001). This Technical Bulletin, troubleshooting, and diagnostic information for the Haldex Infocentre ABS diagnostic box, can all be found by using the following web sites: https://aeps2.ria.army.mil/commodity/pubs/tacom/bulletin/m939_fov.pdf https://aeps2.ria.army.mil/commodity/pubs/tacom/bulletin/m939_infocenter.pdf. F. If problems are encountered at the above links, go to AEPS homepage: https://aeps.ria.army.mil. Use the "Site Search" box at the top and type the word "M939". Press "Enter" and go to articles "M939 FOV Antilock Brake System Tire and Wheel Assembly", also "M939 Infocentre Instruction for Handheld Diagnostic Tool". G. There is a new ABS warning sticker (NSN 7690-01-530-5506) which clearly informs the operator of the meaning of the ABS warning light. Application of this sticker is mandatory, but the equipment still remains fully mission capable (FMC) without it being applied. Units shall order and install individual stickers for their entire density of M939 variants equipped with ABS. In the event stickers are unavailable when requisitioned, they will be backordered and shipped as they become available. H. The new ABS sticker verbiage states: 1. Steady illuminated lamp indicates a malfunctioning anti-lock brake system. 2. If malfunctioning, use gradual braking techniques listed in TM 9-2320-272-10 (Operation W/O ABS). 3. 40 MPH maximum speed with steady lamp. I. ABS warning stickers will be placed on the ledge directly below and centered on the existing ABS malfunction light.
Ensure dashboard surface area is clean, dry and non-greasy before applying sticker.
4. TACOM/PM ACTIONS: {Menu} TM 9-2320-272-10 manuals will require future updates for operator instructions. Updates are forecasted for first quarter 2006. 5. SUPPLY STATUS: {Menu} 32,000 ABS warning stickers, NSN 7690-01-530-5506 have been produced and are available in the supply system.
M923A1 Abs Light
, M925A2 (2320-01-230-030
