Failing brakes on 2004 V70!!! Topic is solved

Juli- failing brakes · Post by **Juli- failing brakes** » 15 Sep 2005, 21:43

In June of 2003 I leased a brand new 2004 V70. Last November I had the Master Cylinder replaced because the brakes froze up for a few seconds (then released and I was able to slow down). In February of 2005 I had the Master Cylinder and Booster replaced for the same problem. Same thing in April of this year, only this time they replaced the Vacuum Pump "just in case." Well last week the brakes froze up on me AGAIN. The dealer told me an engineer who helps develop these cars was in town and would look at my vehicle. He decided it was the Vacuum Pump, so they replaced it. When asked what was causing the problem, I was told that it was an "internal problem that was causing the system to fail", but they don't know why it's happening. HOWEVER, they assured me they don't think it will happen again, and that Volvo would never compromise my safety by putting me back in the vehicle if they didn't think it was safe. How can this be if they don't even know the cause of the problem?? Has anyone had this problem and possibly know the cause?

saltydog · Post by **saltydog** » 16 Sep 2005, 05:43

I used to work for Porsche, & I had a similar experience with a new 911. It ended up being an ABS pump that had an internal manufacturing defect that confused the computer into activating the Porsche PSM. No doubt Volvo uses their own design, but the principals should be the same - has anyone manually inspected any of the ABS components? I know that in the early days of GM ABS set ups, they had a major problem with 'frozen' or 'hard' brake pedals, but that was because that arrangement prevented wheel lock up by pushing back on the pedal itself to moderate the drivers input....poor idea.