Valve-relay fault

The valve relay is integrated in the control unit for traction control. It provides the power supply of the inlet and outlet valves.

With this fault, the DSC indicator lamp, the ABS indicator lamp and the general brake warning light (red) are on.

All traction control functions are disabled and only the conventional brake remains available.

Possible cause(s) of fault:

• The power supply for the valve relay is interrupted (fuse, connector, cable)
  
• The valve relay is defective
  

Storage condition(s):

• The valve relay is subject to continuous self-monitoring by the control unit for traction control.
  

Troubleshooting procedure:

• Check of the power supply of the valve relay (pin 6, terminal 30)
  
• If the fault is currently nor present with an intact power supply or has occurred several times (query to customer), the control unit for traction control must be replaced.
  

Note

• On vehicles of the E38 Series, the SI 61 03 00 562 must be observed.
  
• Renewing the control unit, see Service functions