2005 XC70 ABS Problems

doxster22 · Post by **doxster22** » 29 Dec 2014, 08:02

Ok, I am a long time reader but first time poster with this current issue that I have. First off, the car is an 05 XC70. My problem started when ABS and Brake lights illuminated on the dash along with "Brake Failure -- Stop Safely" showing up on the information center. Doing research, I found that the this is probably due to a faulty ABS module. I ordered a good, used unit (has warranty too) with the exact same part number. Installed module and still have the same issues. I then read that the dealer might have to "re-code" the new module in order for it to recognize it. I took it to my local Volvo dealer and they said that these modules cannot be reprogrammed, meaning I can either buy a brand new module OR have my original module rebuilt.

Does anyone have any input on this or have had a similar situation? Is this true that the module cannot be recoded to fit a different vehicle?

bigbrain · Post by **bigbrain** » 01 Jan 2015, 10:01

I had exactly the same problem with my V70 2wd (with DSTC). I think your options are to have the ABS module rebuilt by sending it off (this is preferable in my view). The second option it to source an ABS module from an identically specced car and hope to get lucky!! I also tried the route of buying (several) ABS modules on line but this was a dead end....the problem is that the part number is only half the issue...the modules will have particular versions of software installed on them....these versions are not encoded into the part number which just describes the module itself. If you do go down the second hand route pull the part yourself to be sure of the car it is coming from otherwise you'll just be buying paperweights. Could be wrong but I believe the XC70s all had DSTC so you will need to "recalibrate" the DSTC sensors....this can be done with VIDA....it does not require a software download. You may be luckier with the XC70 as they all had DSTC....finding a 2wd car with the DSTC option was interesting to say the least. Goes without saying which ever approach you choose it's at your own risk of course....the rebuild would be my preferred route however you should also eliminate other potential causes and don't just assume it's the ABS module at fault....even a loose hub bolt can cause the ABS to go up the spout so its best to get the codes read before laying out any cash.

Post by **doublebug** » 01 Jan 2015, 14:26

look at this flow chart before blaming BCM module.
http://xemodex.com/us/knowledgebase/bcm-flow-chart/

Post by **JRL** » 01 Jan 2015, 21:24

bigbrain wrote:I had exactly the same problem with my V70 2wd (with DSTC). I think your options are to have the ABS module rebuilt by sending it off (this is preferable in my view). The second option it to source an ABS module from an identically specced car and hope to get lucky!! I also tried the route of buying (several) ABS modules on line but this was a dead end....the problem is that the part number is only half the issue...the modules will have particular versions of software installed on them....these versions are not encoded into the part number which just describes the module itself. If you do go down the second hand route pull the part yourself to be sure of the car it is coming from otherwise you'll just be buying paperweights. Could be wrong but I believe the XC70s all had DSTC so you will need to "recalibrate" the DSTC sensors....this can be done with VIDA....it does not require a software download. You may be luckier with the XC70 as they all had DSTC....finding a 2wd car with the DSTC option was interesting to say the least. Goes without saying which ever approach you choose it's at your own risk of course....the rebuild would be my preferred route however you should also eliminate other potential causes and don't just assume it's the ABS module at fault....even a loose hub bolt can cause the ABS to go up the spout so its best to get the codes read before laying out any cash.

You are incorrect on almost all accounts here

bigbrain · Post by **bigbrain** » 02 Jan 2015, 02:05

Really...it would be great if you could list the points you think are incorrect so others can also benefit and we can get factual information into this forum.

Thanks again doublebug for your help last year with this....I couldn't have solved it without your input.

Post by **doublebug** » 02 Jan 2015, 04:06

For an info: any BCM used module can be reprogrammed for any car. Of course if it OK and fits by part number.
Dealers say a new module is required because they have to say that.

Post by **abscate** » 02 Jan 2015, 09:09

Doing research, I found that the this is probably due to a faulty ABS module

I don't this this is accurate. It is more likely that a sensor went bad, a wire got broken, or crap in your sensor wheel interfered with the sensor reading.

The place to research an issue like this is here, on this forum. Buying a replacement ABS used is a crapshoot at best, and, on a P2, is not just a plug and play replacement.

Check to see if mattymoo does P2 ABS replacements - you will get to ABS nirvana much quicker. He posts here regularly.

bigbrain · Post by **bigbrain** » 02 Jan 2015, 10:23

Doxster22 - did you already check the obvious stuff...for example hub bolts are tight/ABS rings clean/Sensors clear etc....you definitely need to do this first as these are cheap/easy. As I said in my original response "you should also eliminate other potential causes and don't just assume it's the ABS module at fault" Replacing the ABS module is not cheap so should be the last thing you should look at. Definitely get the codes read before deciding to throw money at this - this might point you to a particular wheel as the cause. In my case the module was toast but I didn't start at the module!

Post by **jimmy57** » 02 Jan 2015, 10:39

BCM changes 2002 and later are not always programmable. I would say for US market model P2's that they may never be plug n play. There was a change that year where the BCM is built with full software and when car is assembled they get to end of assembly line the BCM is only profiled to the car and not a full download as before. This effectively "marries" the module to that VIN. This change also went along with the brake pedal sensor change to a potentiometer from the previous incremental quasi-potentiometer. XEMODEX and maybe others can do an end run with their equipment but VIDA is picky and looks for several compatibility items before it will communicate with Volvo servers to get the software package.

As others have said, make sure you need a BCM before you go to that trouble an expense.

bigbrain · Post by **bigbrain** » 02 Jan 2015, 12:24

Hi jimmy57 - P2 cars here in the UK are the same so what I did should not have worked! I did have to reconfigure the DSTC sensors (yaw/steering etc) - I didn't have to download software...here in the UK the download onto second hand parts is also blocked by volvo...I have no codes or lights on the dash - the fix was a while a go and no problems since.....sorry it's a volvo I mean no problems with that issue....plenty of other new problems of course!!