Code “C0265”

[Salvador Alasco]

I am re-sending this same problem for your analysis because either I forgot to hit “SUBMIT” the last time or you might have overlooked my mail.
Anyway, my problem is with my 2001 Chevy Tahoe which had been lighting up my dash with the “ABS and BRAKE” lights together.
The first time this happened, I merely shut the engine off and then after a minute or so, I re-started again and the fault lights were gone. The next few days were okay but on the fourth day, the same lights lit up again.
Since I have an scan reader, I plugged the same in the interface and saw a code “C0265” which says I have a problem with the Electronic Brake Control Module (or EBCM) unit. I researched the abnormality and it pointed to a loose or poor ground connection between my EBCM unit and the negative ground chassis of my truck. So I disconnected the ground connection, cleaned the metal chassis connection point, cleaned and scrubbed the ground lug, and then re-screwed back, but this time, I secured it with a lockwasher and a nut for good measure. It went on for a little more than a week until the lights are back on again.
If there was something wrong with the electronic module inside the EBCM, the lights should stay permanently lit, wouldn’t it ? But the fact that lights come on intermittently, what do you think is wrong ?

Topic

[Its me]

I feel your pain on this one. This is a pattern fail for GM that is well known. The ECBMs go bad and work sometimes and not others. I have been living with this for 6 years with my Sierra. There was the TSB about the ground. I did the prescribed repair and it only lasted a short time before the lights come back on.

What needs to be done is either get a new module, but they are very expensive.. or get it rebuilt. There are many places on Ebay that will do this for you for less that 100 dollars. You ship the part, they fix and send back.

The ECBM is easily removed by taking out four torx screws..

Now here is why I have not fixed mine yet, the module is on a rail under the bed and there is about zero access to get to the top fasteners. You may be lucky though because on some GM models they put the module in the engine bay with easy access.

Check out this Web page and search Google more about this… It is too common

https://www.absfixer.com/how_do_i_remove.php

Good luck

Karl

[Salvador Alasco]

HI, Karl ! I see what you mean. I just went under my truck and true enough, the mounting of the EBCM unit is so tight that not only do I need a very short but strong enough TORX ratchet, but I also have to contend with my big hands if it would fit at all into that very small space.
The only possibility I see is to detach the whole EBCM from the rail but I’m afraid I will have to mess with the whole brake system itself, which I am not really an expert on. And then putting it back on and re-bleeding the brake…….whew, the thought alone makes me think what other options I have.
Anyway, I will try to see if I can find a way to remove the torx screws and hopefully get them out. THANK YOU VERY MUCH FOR YOUR INPUT !!

[Its me]

Sorry to hear your EBCM is located in the same place as mine..

Here is what I recommend

Remove the bracket from the frame and ever so carefully pull/twist on the unit for access… It will flex a bit for more room..

Soak the torx screws with PB.. then blow out the holes with air to get all the crap out of there, you want a clean as possible torx head to get a full bite with your torx bit..

Get the proper sized bit on a 1/4 in Rachet and try to break them loose.

Unfortunately those torx screws rust very badly and get really stuck, if you strip them you are in a world of hurt. They are easy to strip, so take your time and get a good solid contact between the head and the torx bit…

Mine are stripped and I will have to drop the unit as a whole… yes that means disconnecting all the brake lines… so that not only leaves you with a full system bleed but on GM’s of this era there is a computer bleed procedure you need a Tech 2 to do or another high end scanner… I have a Modis that will do it, but this whole process is such a pain I have held off and lived with it… perhaps later this summer I will do this and post pics in the how to section…

Karl

[Bill]

This might seem like a dumb reply but have you checked the brake fluid level? Low fluid level can cause both lights to illuminate and may only trigger the brake warning lights under certain conditions.

Sometimes the simple things cure problems.

[John Hugon]

If the brake level is ok….I found this on the Internet; I did this to my truck about three years ago and still ok. Word of caution…it was no fun…but I didn’t want to spend the money: http://www.youtube.com/watch?v=Jo76ylqgUR8

I always had a scan tool to bleed the air out of the BPMV, but I have friends that do side work and don’t have a scan tool told me this works:

Once everything is reinstalled, bleed the brakes as you would any conventional vehicle. When you are confident all the air is out of the lines, connect the vehicle’s battery and start the engine, keeping the vehicle stationary. Make sure that the brake pedal is firm and not spongy. Verify that there are no leaks where the hydraulic lines were re-connected and that the brake pedal keeps it position without slowly dropping to the floor. If all is good, take the vehicle for a low speed test drive. The ABS system will then perform a self check once you exceed 5 MPH and the “ABS” and “brake” lamps should turn off. During this test, the controller runs the pump motor and briefly operates all of the valves. If the brake pedal remains firm, then you succeeded in removing any air left in the system, and you’re done! If the pedal begins to feel soft or spongy, park the vehicle and manually bleed the brakes again. Test drive again, park and repeat the bleeding process until brakes are firm. This ABS “self-test” is performed every time you start and drive.

[Author]

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