05 Yukon ABS Pump Corroded

[ChsCountyYukon]

Hello All. New here. I am working on a 05 Yukon Denali XL 1500 150K. This nightmare started with rusted out brake lines with the ABS / brake light on. I pulled the entire ABS pump out thinking I could just rebuild the module and I ran into a totally corroded pump. The module actually swelled at each screw and cracked the plastic housing of the module. Only 3 screws would come out. I had to drill out one. I assume this pump is toast? How does this even happen. This is not even the worst of it.

 

[Doubeleive]

my first guess would be water damage

 

[ChsCountyYukon]

I am going to buy the pump and module off ebay used. Is that a plug and play deal? Or do I need to have the ABS reprogrammed at the dealer? My original module is shot.

 

[ChsCountyYukon]

Because I had to know I pulled the metal cover off the ABS module. I used a heat gun and razor blades and I still had to hack the surrounding plastic lip up. There is evidence of water damage. Although it is a sealed unit there is a passage on the bottom of the unit that would allow water into the circuit board area. Right underneath the rust is where that passage to the opening leads. There is a rubber seal between the pump and module. If that fails it will allow water to seep in. The truck was purchased used 8 years ago. I am more inclined to think that 15 years of snow and wet weather had its way. The real question is why on earth is an ABS module located under the chassis. I found a replacement pump with module. Should be here in a week. I will let you know how it goes.

 

[SnowDrifter]

While you won't need to have the pump reprogrammed, I would suggest having the brakes bled at the dealer or independent shop with a scan tool capable of putting the system into bleed mode. There are a lot of channels and solenoids in the thing internally and unfortunately, you won't be able to get the air out without cycling the thing

 

[ChsCountyYukon]

The ABS pump was replaced. I had to bleed twice to get a firm pedal, it is now perfect. I can now communicate to the ABS module. I was unable to communicate before. Here is the latest issue. During this repair job I replaced the right front speed sensor due to an error code before any of this work started. During the leaking Hydraboost replacement I broke the brake pedal sensor. I replaced both parts. ABS / Brake light are now off. After starting the truck and driving it forward the traction control engages and ABS light is back on. The error code on the ABS unit is C0040 Brake Pedal Switch A. I used low cost parts off of Amazon. I am not sure part is the problem. I am thinking I still have an issue with the front right speed sensor or maybe even the hub is bad. The wheel does not rock in any direction.

ABS part # is 13642516T. I did find this exact used part # off eBay. That did include the pump. I paid $179. That was on the high end but the pump was from a dry region that does not use salt on the roads. I do not know if the exact part matters but I thought it would increase my chances of success if I did a like for like swap. There was no reprogramming required. My ABS light went off on next startup. I did not require the use of a Tech II to bleed the brakes. I was able to complete this with the Motive power bleeder. You will also need a Proportioning Valve Bleeder tool. Picked one up off eBay for $5. Part # 91664082. You unscrew the sensor and screw in this little tool. This will allow fluid to flow to the back lines and through the ABS unit. That did about 90% of the job. I took the truck to a gravel parking lot and locked up the brakes to activate the ABS. That took care of the remaining 10%. You will need to bleed the brakes at least twice. On the first bleed my pedal still went to the floor. Let the car site for a few days and monitor for any leaks. I had a few that were solved with tightening down the lines a little more. Don't loose faith here. Bleed the system twice.

I replaced all steel brake lines. I used the kit CNC-150KIT with RPO Code JL4 (Active Brake Control). I purchased this kit online at advanced auto and used a 25% off coupon. I paid around $110. This kit was perfect. They give you plenty of extra length on the lines. On the front lines I did have to put a loop in due to excess length. I opted to keep the original flex lines from the master cylinder to the proportioning valve. Existing lines were fine and this allows maintenance space if I need to pull the master cylinder in the future. Looking back I would have ordered those flex lines and replaced them while I was there. The kit includes the copper lines that replace the flex lines.

 

[ChsCountyYukon]

Here is where I am at. The front passenger side hub is not original previous owner must have replaced it. It had shims and that is not OEM. When I look in the ABS hole it is clean and I can see the tone ring. I pulled the speed sensor on the driver side (no shims) and looked in the hole. It is filled will dirty grease covering the tone ring. If this does not fix the issue then its off to the bone yard.

 

[ChsCountyYukon]

The passenger side hub was aftermarket. Part # 515036. Made by MOOG. This part is at least 8 years old with 80K miles on it. I replaced the hub with one that already had a speed sensor installed. No more ABS lights and Stabilitrak lights are off. The old hub seemed fine. There was no play. Something internal was setting off the speed sensor. I think aftermarket hubs are tooled and calibrated to only work with their ABS sensor. While I was there I did replace both hubs. Get yourself an air hammer for this job. Worth every penny when you can remove the old part in 3 minutes. The driver side hub was leaking grease. There was grease everywhere. Not to mention the hub was rusted out. It is much quieter now up front.

I purchased 2 replacement hubs off eBay from Detroit Axle for $75. I also purchases a brake pad and rotor kit for $140. Fit perfect.


Here are all of the codes I had at the start of this job that are now gone one week after completion.

With the ABS and Brake light on the following codes were present.
P0856 - Traction Control Torque Request Circuit Malfunction
U1041 - Loss of EBCM Communication
C0040 - Right Front Wheel Speed Sensor (replace the hub with speed sensor)
C0550 - ECU Performance
P0240 - Traction Control Not Allowed
C0244 - PWM Delivered Torque Malfunction
P0279 - Pre-charge Pump Circuit
C0131 - ABS/TCS System Pressure Circuit

Unrelated (I am sure these will return)
P0462 - Fuel Level Sensor
P0455 - Evap Leak

Parts Used

BLS-401 - Stoplight Brake Light Switch - with Adjustable Pedals - (Amazon)
52-7370 - Remanufactured Hydroboost by Cardone - (Amazon)
25846360 - Front caliper bleeder AC Delco - (Amazon)
88967108 - Rear caliper bleeder AC Delco - (Amazon)
21998448 - Brake Combination Valve AC Delco - (Amazon)
515036 - Detroit Axle- Both Front Driver & Passenger Side Wheel Hub - (eBay)
YL-924-517 - Spare Tire ***** - (eBay)
13642516T - ABS Pump - Includes the Module Used - (eBay)
H620451 - Brake Hose Rear Center Lines to ABS. Over Axle. Dorman Need 2X - (Amazon)
H620833 - Brake Hose Rear Lines to caliper. Dorman Need 2X - (Amazon)
H620441 - Brake Hose Front Driver to caliper. Dorman - (Amazon)
H620442 - Brake Hose Front Passenger to caliper. Dorman - (Amazon)
781PG - Parking Brake Raybestos - (Amazon)
H7322 - Parking Brake Hardware Raybestos - (Amazon)
CNC-150KIT - EZ-Fit NiCopp Brake Line Kit - (Advanced Auto)
BK91000408 - Detroit Axle - 6-Lug FRONT & (330mm) REAR Brake Rotors & Ceramic Brake Pads (Amazon)
91664082 - Proportioning Valve Bleeder Tool (eBay)
Brake Caliper - Used off (eBay)



I think this is the kind of issue that puts a vehicle in the bone yard. I am a weekend mechanic at best and with plenty of time I was able to get it done. My advice. Get an air hammer.

 

[ChsCountyYukon]

I thought I would add in a helpful tip plus I found some pictures on my phone. I did this job on the ground without a lift. When changing out the rear center flex lines above the rear axle, access is close to impossible. Remove the two brackets that hold the lines in place. You can get access to the bolts holding the brackets down. Assemble on the bench and then reinstall as one. The Dorman hoses did not have the exact fitting that would allow it to sit flush in the brackets to secure with the clips. I drilled the holes out that did not fit the lines. That allowed the hoses to sit flush and secure. Do not mount the lines until you replace the lines going to the rear wheels. A few extra inches of wiggle room will save you a ton of frustration. If I had to do over I would have went with OEM rubber brake hoses and just paid 2X as much.