Subject: Re: E39 ABS/DSC System puts all 4 brakes on Author: jimcash : member since July, 2005 : 1384 posts Posted on: 2009-08-22 11:54:44

You say this has been "in the garage" and they do not know what is wrong with it.

Was this a BMW service garage and did they connect it to the BMW DIS system to read the fault codes?
If so this should be pointing to one or more specific reasons why the warning lamps are on. It should not be necessary for you to be changing components (IE wheel speed sensors) if they are not showing fault codes - if there is one defective there should be codes for that wheel)

According to the VIN your car is a Euro version with a Dec 97 production date - so it should be DSC - but then the systems do vary by country.

It almost sounds like there may be a fault in the master cylinder or the brake assist that is causing the system to think the brakes are being applied - or that pressure is building somehow.
This version of the DSC has a "pre-charge pump" under the hood which may be operating after it should, and there is an RPM sensor and an acceleration sensor - both under the carpet under the driver's seat area.

Also involved is the brake pedal switch which, also influences the operation of the pressure pump.

The system is rather complex with many items affecting the operation and unless you have the fault codes read then you are only guessing what the problem might be - that can be time consuming and costly.

Cheers
Jim Cash

• E39 ABS/DSC System puts all 4 brakes on - mpweston 2009-08-20 15:05:24 (227 views)
  • Re: E39 ABS/DSC System puts all 4 brakes on - jimcash 2009-08-22 11:54:44 (110 views)
    • Re: E39 ABS/DSC System puts all 4 brakes on - mpweston 2009-10-09 06:06:41 (45 views)
      • Re: E39 ABS/DSC System puts all 4 brakes on - jimcash 2009-10-09 15:16:37 (55 views)
        • Re: E39 ABS/DSC System puts all 4 brakes on - mpweston 2009-10-10 17:01:20 (35 views)
          • Re: E39 ABS/DSC System puts all 4 brakes on - jimcash 2009-10-10 17:18:11 (32 views)