New MVS Contributor ReWagner posts a great PDF that shows how to remove and replace the ABS pump in P2 Volvos…
For some time I have had an ABS message – with trouble codes BTM0070 (pump motor supply voltage, faulty signal) and BCH0072 (pump motor, mechanical error). The online information that I could find suggested that the likely problem was a faulty Brake Control Module.
At first the ABS message was intermittent, then continuous. I got a used BCM and replaced the old one. That solved the problem for a while, but it became intermittent again, then continuous.
I sent the original BCM to XeModEx and had it rebuilt, to repair the power leads and to put a more robust pump driver in it. That solved the problem for a while again, but the ABS message soon returned intermittently. I called XeModEx and they told me that often the pump motor is faulty, rather than the BCM.
So I bought a used ABS pump motor and replaced the old one. That has solved the problem.
I am posting because I could find no reliable information on how to replace the ABS pump motor itself, without taking the entire ABS pump assembly out of the vehicle. That would have required the brake lines to be removed from the ABS pump assembly, and when the ABS pump assembly is reinstalled the brake lines would need to be bled.
Instead, I found that it is possible to remove and replace the ABS pump motor without taking the ABS pump or the BCM out of the vehicle. That avoids the need to remove the brake lines from the ABS pump, so it is not necessary to bleed the brake lines after the repair.
I am including what I learned about how to make the ABS pump motor replacement in the attached document. There are some photos in the attachment that may help understand how to do it. Perhaps this information will be useful to someone with the same problem.
The ABS Pump Replacement PDF:
2005 Volvo S60 ABS Pump Assembly Motor replacement. See this Volvo Forum topic: 2005 S60 ABS Pump Motor Replacement. The PDF link is in the first post.
In order to get to the pump, do the following:
- Remove the positive terminal from the battery in the trunk
- Remove the air filter box
- Disconnect the electrical connector to the mass airflow sensor
- Remove the air vent tube from the air filter box
- Remove the air filter cover and take the air filter out
- Pull up on the three plastic capture fixtures to release the box
- Move the box out of the way
- That exposes one of the two fuse box mounting bolts
- Remove the fuse box
- Remove the 10mm exposed mounting bolt from the fuse box
- Take off the fuse box cover
- Take off the positive terminals by removing the attachment nut
- That exposes the other fuse box mounting bolt in the recessed hole
- Remove the second 10mm mounting bolt down in the hole
- Slide the fuse box toward the engine to release the mounting slot
- Move the fuse box out of the way
- Remove the brake control pump motor
- Remove the three bolts that mount the pump block to its bracket
- Use a Torx T30 male driver for this
- There is not much room, but it can be done
- That releases the pump from its bracket, so it can move a little bit
- Don’t move it too much, because you don’t want to bend or break the brake lines that are attached to it.
- Move the pump unit about 1?4” toward the front of the car to expose one of the two motor mount bolts that is obscured by the bracket
- Remove the two motor mounting bolts using a T25 Torx driver
- The motor will come free if you wiggle it off the aluminum block
- No brake fluid leaks out, because the pump is sealed from the motor
- Be careful not to remove the bearing inside the aluminum block
- If you do remove that bearing, it is difficult to put back
The pump motor has two brushes that are worn so it won’t operate properly. The brushes can be replaced or the pump motor can be replaced with a used motor.
How the ABS Pump Works
Applies to S80, V70, XC70 and XC90 Also
The parts and procedure is similar or identical to these Volvos:
- 1999–2006 Volvo S80 (P23),
- 2001–2007 Volvo V70 (P26E),
- 2002–2007 Volvo XC70 (P26L),
- 2003–(current) Volvo XC90 (P28)