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2005 XC90 Front Passenger Brake Locks Up – Fix

Dale’s front right brake on his XC90 is locking up when he uses the brakes. This is a really serious problem, I think it goes without saying but here we are saying it anyway. What MVS Moderator Joe found for his 2004 XC90 brake lock-up problem was the problem was in his XC90’s BCM/ABS unit’s valve component.

He explains how to fix it here.

2005 XC90 brake BCM / ABS unit
BCM / ABS unit consists of 3 parts: BCM module, motor, and valves (aluminum block in between the other two items.)

MVS member Dale:

Brand new to this site and I really need some HELP !! I can loosen bleeder and the caliper releases the hold on rotor {can pry the piston in with bleeder cracked open}. The caliper seems ok ? The caliper moves on the pins good {left to right} I even changed out the rubber hose going to caliper as it looked s little rough, did NOT help the sticking ? Any ideas ? As soon as I hit the brakes front wheel locks up.

MVS Moderator joejoethedogfaceboy shows how to close in on the problem like a laser.

Had almost the exact same problem with my ’04 XC90 about a year ago, except mine was the driver side. You’ve done the correct troubleshooting so far, but now you need to keep working your way towards the brake master cylinder. The next thing in line is the ABS Brake Control Module. This is the bit that was broken for my car, and you might have the same issue. One of the valves was sticking and not releasing. Here’s a very rough outline of what to do next:

On the brake control module, there are 4 brake lines that go to each corner of the car, and then 2 lines that go to the master cylinder. Start the car and push on the brakes so the front passenger “locks”. Shut the car off. Find the line coming from your passenger brake caliper – one of the 4 along the bottom – (sorry, I don’t remember what order they are in, but you can probably google it or trace the brake line) and crack it open. (put some paper towels underneath to catch brake fluid.) If the brake releases, then you can assume the caliper and line to the caliper are fine. Tighten the brake line back up.

Joe goes on to narrow down the problem on his 2004 XC90:

I initially sent the entire package to Xemodex for a rebuild, but they don’t do anything with the valve block – just the control board and the motor – so it didn’t fix my problem. I got a BCM package from a local junk yard, and swapped out the parts. The BCM circuit is programmed for your car, so you need to swap out the control board from the original package. You can get details on taking the module apart on the Google.

VRD: 2005 XC 90 front passenger brake locked up

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