abs control unit

[rstraus]

I have a '99 Sierra Z71 and my antilock break pump stayed on even when my keys were turned off. I found out that this a very common problem and it concerns a short in the abs control unit. I bought a new unit and now I am going to put it in. Does anyone know if it is a big deal to put in. If someone has did this before could they please give me some helpful hints or instructions. Thanks!

Rick Straus

[99GMC]

that sucks man, I know how you feel my 1999 gmc sierra has the same problem, I still haven't purchased that replacement part yet. I've herd that your best bed would be to take it to a shop or a dealer because it deals with bleeding the brakes and some very detailed electrical work.

[bowtiebandit]

If it is done correctly it doesn't require any hydraulic work nor electrical.
Just the use of a scan tool....

EBCM replacement

After installation, calibrate the new EBCM to the tire size that is appropriate to the vehicle. Refer to Tire Size Calibration portion of ABS Description .

Negative Battery Cable.

Important
Thoroughly wash all contaminants from around the EHCU (1). The area around the EHCU MUST be free from loose dirt to prevent contamination of disassembled ABS components.

Disconnect the electrical connectors from the EBCM.
Loosen or Remove 3 bolts (4) securing the EHCU mounting bracket (3) to the frame rail (5).

Gently move the EHCU down enough to remove the four T 25 Torx® mounting screws that fasten the EBCM (2) to the BPMV (1).
Remove the EBCM (2) from the BPMV (1). Removal may require a light amount of force.

Important
Do not use a tool to pry the EBCM or the BPMV. Excessive force will damage the EBCM.

Clean the BPMV to EBCM mounting surfaces with a clean cloth.
Installation Procedure

Important
Do not reuse the old mounting screws. Always install new mounting screws with the new EBCM.

Important
Do not use RTV or any other type of sealant on the EBCM gasket or mating surfaces.

Install EBCM (2) on to the BPMV (1).

Notice
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

Install the four new T-25 Torx® screws in the EBCM (2). Tighten
Tighten the four T-25 Torx® screws to 5 N·m (39 lb. in.) in an X-pattern.

Install or tighten three EHCU bracket mounting bolts Tighten
Tighten the EHCU bracket mounting bolts to 25 N·m (18 lb in).

Connect the electrical connectors to the EBCM.
Connect negative battery cable.
Revise the tire calibration using the Scan Tool Tire Size Calibration function. Refer to Scan Tool Diagnostics .
Return to Diagnostic System Check - ABS .

[jdod85]

my 1999 GMC had the same problem. Luckly it was under warrenty. it cost $785 to get it fixed at the dealer.

[Gavin Curtis]

If you have a pump motor running all of the time, get your ABS unit REPAIRED for a flat service fee of only $100 which includes all parts and labor.

Goto www.circuitsolutions.info and click on the "ABS" logo at the top.

You will still be able to drive your vehicle while the EBCM is in for repair. You will get your original EBCM back with all of its internal EEPROM settings unchanged. You will not have to deal with the calibration tool. The repaired EBCM will perform an extensive self-diagnostic on its own once installed - no external diagnostic tools are necessary to initiate this self-test.

Both the ABS and BRAKE lamps will extinguish as long as the rest of the vehicles ABS system is fully functional (sensors etc); all ABS functionality will be fully restored. The repaired modules use significantly better parts to eliminate any future pump motor control problems within the EBCM.

The repair is permanent.

All work is guaranteed.

[bobby81001]

I Had Gavin Curtis At Circuit Solutions Repair My Faulty Ebcm For 100.00 Plus Shipping Both Ways. Its Been 2 Weeks, So Far So Good, After Installing The Fixed Unit Both Lights (abs And Brake) Went Out And The Pump Quit Running After The Truck Was Shut Off. I Haven't Had A Chance To Test The Abs System To See If It Is Working, I Need To Find A Dirt Road Where I Can Slam On The Brakes To Test It.
I Will Post Any Problems That I Have In The Near Future.

If You Have A Abs Pump That Wont Stop Running After The Truck Is Shut Off, I Recommend That You Go To Circuit Solutions Web Site And Consider Having This Done. Their Q&a Page Will Answer Alot Of Questions About The Problem. I Didn't Remove The Whole Pump Assembly Like They Recommended I Just Removed The Ebcm. Its A Little Hard To Get To. Keeping Everything Clean Is Very Important.

Good Luck Rob

[jconrad]

Hi all,

just found this forum. My wife got home same time I did tonight and said "..the truck's making a funny noise". Something was running, even with the ignition off. Thought it was maybe fuel pump but pulling the relay made no difference - yanking the ABS fuse (after hearing that the light was on) stopped it.

So, looks like I have exactly the same problem (99 Z71) as everyone else on this thread is describing. I've quickly skimmed through the replies - any consensus on the best fix and is there 1-fix-for-all? Seeing a $800 total scares me since it's sure to be $1000+ in Canada.

Any info appreciated!!!

[Gavin Curtis]

The ABS controller that is making your pump run constantly can be fixed permanently for $100. Go to www.circuitsolutions.info and click on the "ABS" icon for details regarding module removal and where to send it.

Many Canadian neighbors now have working ABS systems once thought to be too expensive to repair.

[GRSZ06]

Does anyone know the GM part number for this unit?? I ahd a dealer tell me I had to replace the modulator valve for 850.00....so before I send this off to get repaired for 100.00, I want to be sure our descriptons are apples for apples... I have the pump running all the time

[jdod85]

Originally Posted by GRSZ06

Does anyone know the GM part number for this unit?? I ahd a dealer tell me I had to replace the modulator valve for 850.00....so before I send this off to get repaired for 100.00, I want to be sure our descriptons are apples for apples... I have the pump running all the time

The EBCM # is 88935723. That is the number from my W/O. It was done on my 199 GMC

[miguelcl]

I also have this problem and will use the 100 buck fix. I am here to
urge everyone with this problem to write and call the NTSB and file
a complaint against GM. The more there are the better the chance of a recall.

[hoss4]

Any idea where you can find the 4mm dia - 25 mm long T-20 torx screws that hold the EBCM? I could only find them at the dealership, and they wanted $6.00 per screw.

[Joe Worthington]

Hey, You guys needs to check out http://www.absfixer.com they just repaired my EBCM for the pump running problem and everything works great now. They charge a bit more but they also offer overnight return shipping which in the end is comporable to circuit solutions.

Thanks to these great repair companies!!!

[Dreamer401]

Check out modulemaster.com ... much much much MUCH more info than anyone else I've found so far. Very helpful.

Later...

KC

[Sonny01]

You can get stainless screws form Curtis at www.circuitsolutions.info He saved me about 1500.00 in repair bills to my ABS system when the light went on and I had a bad pump and needed my EBCM repaired. I had to have the screws cut off so I needed the stainless ones. Any questions please drop me an email.
Sonny