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Daniel Wilson
Daniel Wilson,
Category: Medium and Heavy Trucks
Satisfied Customers: 5424
Experience:  Owner at DJ Wilson
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05 Freightliner Columbia. Has ABS problem. When ignition is

Customer Question

05 Freightliner Columbia. Has ABS problem. When ignition is in ON position "Tractor ABS" light comes on and stays on. LCD on dashboard reads NO_ABS when I push and hold button on cluster instrument panel it reads Fault 1, sid 254 fail 07. ABS test switch won't make light blink. It only dims it for as long as you press it. I checked the fuses in both PDMs (main + B pillar) all seemed good. Checked wires and harnesses but couldn't find anything unusual. Hooked up a DPA5 adapter to 9-pin connector and scanned with meritor wabco Toolbox software but ABS was not detected (tried 2 ABS modules). I was able to connect to ECM though. Any idea?!
Submitted: 1 year ago.
Category: Medium and Heavy Trucks
Expert:  Daniel Wilson replied 1 year ago.

Hi my name is ***** ***** will be glad to help. Check for a loss of power to the ABS or from the PDMs. That fault is for a loss of power.

Your power circuits should be 376a and 376c1 into the B pillar PDM and 376a should be pin 8 at the ABS ECU plug and 376c1 pin 7.Pins 4 and 9 are grounds.The only wiring that goes through the plug on the bottom of the cab are for the sensors and ABS solenoids, all your power supply and ground wires for the ABS ecu are routed in the cab.Circuit 1204(GROUND) goes to a stud in the B-pillar. The schematics will help identify the wiring and terminal pin locations in the connectors. Confirm the voltage to battery voltage using a volt meter instead of a test light in case you are getting under battery voltage in the circuit as well. Test your grounds with an OHM meter. Let me know

Customer: replied 1 year ago.
I need diagrams please. I am not a technician. Just trying to DIY. Thanks
Expert:  Daniel Wilson replied 1 year ago.

Click on this link for some diagrams to help in troubleshooting.


Expert:  Daniel Wilson replied 1 year ago.

Do have a complete electrical Manual for the Columbia I can offer at a premium service if you are interested I will post the offer. Review what ive posted and let me know if you need further schematics.

Customer: replied 1 year ago.
Do you have a diagram for the B pillar PDM as well?
Customer: replied 1 year ago.
By the way the B pillar PDM on my truck is different from the one in the pdf. last 5 of my vin # *****
Expert:  Daniel Wilson replied 1 year ago.

Click on this link.


Customer: replied 1 year ago.
Is it normal that only 5 connectors are attached to my auxiliary PDM. Missing connector referred to in last pdf as connector P3. Also, I only have fuses on the B pillar PDM. No relays nor circuit breakers.
Customer: replied 1 year ago.
Connector P4 has only 1 wire in it.
Customer: replied 1 year ago.
I am wondering why my last question was not answered. Are you still there?
Expert:  Daniel Wilson replied 1 year ago.

Hi, I help on here in between jobs and as I am able. Experts are not employees of the site. Experts only get credit for their time on accepted answers and positive feedback for a percentage of the question value. It is a holiday weekend and I am with my family who is visiting for the long weekend. I have not had time to look through the schematics as of yet to walk you through this.

Expert:  Daniel Wilson replied 1 year ago.

Let me know if these match up to your PDM better.

Customer: replied 1 year ago.
I never said you were an employee of this website. I was promissed an answer in less than 30 minutes. My last question was answered after almost 24 hours. I could have waited if you gave me heads up that you were with family or needed more time to investigate. But not to say anything at all although you were showing online is totally different. You could have saved your spiel if you communicated better.
Expert:  Daniel Wilson replied 1 year ago.

I have nothing to do with how the site advertises and their communication to you other than what I type in this chat. I was at the White mountains in NH all day so I was definitely not logged in here so that is a technical issue with the site. Ill opt out so someone else can help you sooner. Good luck.