Silverado C0265 Repair

a_kelley

mechanical fixer
Joined
Jan 26, 2010
Location
Rutherfordton
OK so I figured since I had to repair a c0265 (pump relay failure) on a 2000 silverado 1500, I would document it and post it. You're supposed to replace the electronic brake control module for this code, however, you can repair it with some patience.

You'll need:
  • A 90* pick
  • T8 bit (long)
  • T20 bit (short)
  • T20 bit socket
  • 1/4" (ratchet) wrench & 1/4" ratchet
  • Micro torch
  • 100w+ Soldering gun(optional)
  • Fine flux core solder (.060 of your choice. My preference is lead/tin, seems to wet better)
  • Isopropyl alcohol/non-chlorinated brake cleaner (to remove flux residue)
  • Heat transfer grease (not required, but recommended)
  • Good eyes
  • Bright light & magnification
  • Steady-ish hands
  • Razor blade/knife
  • Sealer (my preference is ultra grey, but you can use anything just so long as it does not smell like vinegar)
Now that you have your tools assembled, remove the EBCM from the hydraulic module. There are four T20 bolts, from the top side of the unit. You do not need to loosen any hydraulic lines to do this repair. Unplug the three electrical connectors. Clean the torx bolt heads before attempting to remove. You can use a regular bit/socket on the frame side two, but the other two you need to use just the bit and a wrench to have access to remove them. Gently lift up the module and remove it from the vehicle.

(No pics this step.)

Now that it is removed, lay it bottom side up and remove the six T8 bolts holding cover on. Not all units have bolts, depending on version.

IMG_20191231_002322608.jpg



Put the EBCM edgewise on the bench and take your razor and slice the sealer holding the cover on. All units are sealed shut. I try to take several passes to get 3 sides cut most the way through and gently pry and you can easily get it open. It takes a little patience.

IMG_20191231_002341039.jpg

IMG_20191231_002426758.jpg



After it is split open and its innards are now outwards, you can resolder the cracked solder joints. Depending on revision this may differ from my board. However, generally it is the joints for the connectors and the relay. You can see them circled and will be similar in all units. You can use the micro torch for all the joints, as long as you are careful to only heat it enough to remelt the solder and add a little more. My 140w soldering gun did not have enough heat to satisfactorily resolder the connector joints.

Connections to inspect:
IMG_20191231_002443098.jpg



Cracked joint.

IMG_20191231_002817075.jpg


Soldering joints:

IMG_20191231_003020259.jpg

IMG_20191231_003600544_HDR.jpg



Resoldered joints & ready to assemble. Make 100% certain that you do not "bridge" joints by adding excess solder. Should you happen to bridge a joint, fine strand copper wire or copper wire braid will help to remove it (with additional flux to help the braid/wire draw the solder).

Once you have them resoldered the cracked joints and cleaned the flux off (and any others you wish to retouch while in there), put a dot of heat transfer grease on each white spot on the inside of the cover (if you dont have any, don't worry too much about it, as the ABS module only activates for short periods of time and I haven't had any longevity issues with not adding more grease), skim coat the perimeter of the lid and reassemble. Wipe off excess sealer that mushes out so you don't wear it reinstalling the EBCM.

IMG_20191231_003808902.jpg



Reinstall EBCM to hydraulic module.

Reset the EBCM codes & run a automated bleed to verify the repair. In absence of a scan tool, you might get by unhooking the battery or just test driving it. The first time you drive at 5-15 mph, the computer runs a brake test. You may have noticed the ABS & brake light does not come on immediately even when it is not working properly - that is due to the self test occurring while moving.

Final step - Enjoy not seeing the ABS & brake light being illuminated & ABS working. Considering the EBCM runs about $150-350, I'd say that its worthwhile to repair the module you already have that is failed. If you are scared of soldering, simply remind yourself that at worst, if you screw up, it blows a fuse, and does not work.

DISCLAIMER: Any repairs following this procedure are your liability, not mine. If for some reason in the course of you following this repair your truck burns to the ground, brakes fail while driving, you burn or cut yourself, it's entirely your problem and not mine. You assume all responsibility and liability from any and all successes and failures or any consequential or incidental or accidental damages, whether intentional or unintended. That being said, you should succeed in your repair if you reflow all the broken joints , unless the module is truly FUBAR'ed.
 
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@Paul - this was your module that I documented.

I have contemplated sharing this tech for awhile... nearly every Silverado 1999-2004 will have this fault at some time or another. I have not had any units with a C0265 failure that was not able to be repaired in this manner. This repair may apply to newer model vehicles as well, although I have not had any brought in to confirm that it happens to any later models. The EBCM is similar on 1500,2500,& 3500 trucks. It also applies to Tahoe/Trailblazer/etc that is setup with the ABS module down under the vehicle by the transmission/transfer case.

Oh, this also is a VERY similar repair to what is required to fix a XJ/ZJ ABS module. slightly different, but it's very much similar failure, cracked joints on the relay and power/pump connector. So I would think that it would also be similar to a TJ or any other vehicle. As long as the EBCM/ABS module is mounted directly to the pump/valve block, this tech will apply, though the exact solder joints will differ in location. You can inspect them and if any are failed, retouch them, reassembe & test.

Hopefully the remanufacturers of the modules don't get mad at me for disclosing the method to repair these modules.
 
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I'm actually going to be doing this exact thing on my neighbors 2000 Sierra that's the boat tow rig. It's needed it for a while.
 
I need to do this, as well as the shift indicator in the cluster. Thanks for the write up!
 
@Paul - this was your module that I documented.

I have contemplated sharing this tech for awhile... nearly every Silverado 1999-2004 will have this fault at some time or another. I have not had any units with a C0265 failure that was not able to be repaired in this manner. This repair may apply to newer model vehicles as well, although I have not had any brought in to confirm that it happens to any later models. The EBCM is similar on 1500,2500,& 3500 trucks. It also applies to Tahoe/Trailblazer/etc that is setup with the ABS module down under the vehicle by the transmission/transfer case.

Oh, this also is a VERY similar repair to what is required to fix a XJ/ZJ ABS module. slightly different, but it's very much similar failure, cracked joints on the relay and power/pump connector. So I would think that it would also be similar to a TJ or any other vehicle. As long as the EBCM/ABS module is mounted directly to the pump/valve block, this tech will apply, though the exact solder joints will differ in location. You can inspect them and if any are failed, retouch them, reassembe & test.

Hopefully the remanufacturers of the modules don't get mad at me for disclosing the method to repair these modules.

Hell Yeah!
That damn abs light has been on for ten years at least.
Thanks dude.
 
Bleeding these are a pain in the ass too..
 
I've never had issues like you did.. of course I've got the scanner to do it with.. and start at the master, then to the valve block, then wheels, then automated bleed.

I have a scanned, did just like you stated. Still haven't gotten all the air out.
 
I done this today, I think. I removed the module, re-flowed all the main spots (feel like I did a good job) sealed back up and replaced it. Lights are still on, but I’m waiting on my buddy to get here now with a scanner to reset it and see if that fixes it.
If not I guess it was a failed attempt, but I only wasted $17 on a soldering kit which I needed anyway and with the help of YouTube sharpened my soldering skills.

I’ll update shortly if the rest works.

Also it looks like I will not be fixing the shift indicator, because it’s different than 99-02 and you have to remove the gauge needles and I’m just not willing to risk breaking those and not having accurate gauges!
 
You have to drive it for it to self test and turn the lights off.

As far as the gauges go, I could do another write up on them. It's not that bad of a repair.
 
Put about 6-10 miles on it so far, still there. Scanner said it still has ECU fault. Guess it didn’t work.

I would love a write up in properly removing the gauges. I’ve watched videos, and a few people broke the gauges so they had to replace the servo. I’m really afraid of that but with the right instructions I might try it. Really scared of removing the needles. I’ve messed one up before.
 
Did you try clearing the codes and trying a automated bleed? And do you happen to have any pictures of the board before/after? Did the terminals for the motor and power input fully reflow? I had to use the micro torch I had to get them to fully reflow.
 
Did you try clearing the codes and trying a automated bleed? And do you happen to have any pictures of the board before/after? Did the terminals for the motor and power input fully reflow? I had to use the micro torch I had to get them to fully reflow.

I didn’t take any pictures, but I did look in thru the side and see that they reflowed well. It doesn’t take long at all to take it off and open it up again.
 
After watching a video again, I may have not put enough focus on holding the iron on there with the intention of it actually getting hot enough to let the solder flow below the surface of the board. I think I realized the need for that about 2/3 of the way thru. I may try again tomorrow afternoon, doesn’t cost me anything but time. If that doesn’t work I’ll hang it up and plan to buy a refurbished unit later on.
 
After watching a video again, I may have not put enough focus on holding the iron on there with the intention of it actually getting hot enough to let the solder flow below the surface of the board. I think I realized the need for that about 2/3 of the way thru. I may try again tomorrow afternoon, doesn’t cost me anything but time. If that doesn’t work I’ll hang it up and plan to buy a refurbished unit later on.
first one I did, I tried using my soldering gun but it didn't get hot enough to fully reflow. Took it back apart, and hit it with the little torch till it fully reflowed and it was good.
 
first one I did, I tried using my soldering gun but it didn't get hot enough to fully reflow. Took it back apart, and hit it with the little torch till it fully reflowed and it was good.

Perhaps @adamk will let me use his torch one soon and I’ll give it another shot.
 
All you need is a 3.99 micro torch from a gas station. It doesn't need a tip on it, just a fine flame.

Shoot I seen those at the Dollar General. I’ll pick one up and report back.
 
Tried again today with the micro torch. Torch certainly penetrates the heat better. The first time I didn’t grasp the fact that I was supposed to heat it to a point that it will actually flow the solder below the board. Essentially trying to solder the opposite side of the board. This time I could get it hot and wiggle the prong and see the solder sit down as it flowed. Then looking thru the side I could actually see where I’d successfully “re-flowed” the joint.

Nevertheless, I still have the light after driving about 6 miles. I’ll try the battery test but I’m certain the light will remain on. I’ll either replace the module one day or live with the light. If you were closer I’d gladly pay you a visit.
 
Tried again today with the micro torch. Torch certainly penetrates the heat better. The first time I didn’t grasp the fact that I was supposed to heat it to a point that it will actually flow the solder below the board. Essentially trying to solder the opposite side of the board. This time I could get it hot and wiggle the prong and see the solder sit down as it flowed. Then looking thru the side I could actually see where I’d successfully “re-flowed” the joint.

Nevertheless, I still have the light after driving about 6 miles. I’ll try the battery test but I’m certain the light will remain on. I’ll either replace the module one day or live with the light. If you were closer I’d gladly pay you a visit.
now, the abs module should self test as soon as it hits 5-15 mph.. you should be able to hear the pump come on (if your exhaust is quiet as stock anyway). There is possibly other things that can go wrong with the units, this is just the most common issue. If you could scan it with a quality scanner you could see if the pump comes on, cycle the valves, etc.
 
now, the abs module should self test as soon as it hits 5-15 mph.. you should be able to hear the pump come on (if your exhaust is quiet as stock anyway). There is possibly other things that can go wrong with the units, this is just the most common issue. If you could scan it with a quality scanner you could see if the pump comes on, cycle the valves, etc.

The last 2 scanners that I’ve used said ECU failure. Basically it can’t even complete the self test because of the failure is my understanding.
 
The last 2 scanners that I’ve used said ECU failure. Basically it can’t even complete the self test because of the failure is my understanding.
correct. So it's possibly a failure of one of the chips or drivers. As far as I know there's not much of any way to get detail on the failure, at least with "dealer" level tools.. factory level, probably. I may have a unit kicking around, I'll check
 
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