Checking the power supply and ground for the brake control module (BCM)

Fig 1: Identifying Ignition ON

Courtesy of VOLVO CARS OF NORTH AMERICA.

• Ignition on.

  Check the fuses in the fusebox in the engine compartment (30-supply) for the brake control module (BCM).

  NOTE:

  If any fuses are blown, check the circuit after the fuse for a short-circuit to ground before replacing the fuse. Then replace the fuse.

  Check the fuse in the fusebox in the passenger compartment (15-supply) for the brake control module (BCM).

  If the fuse is blown, check the cable between the brake control module (BCM) and the fuse. Check for a short-circuit to ground.

  If the fuse is intact, check the cable between the control module and the fuse. Check for an open-circuit.

  Check the ground lead between the control module and the ground terminal. Check for an open-circuit. Also check the ground terminal. Check for contact resistance and oxidation.

  Remedy as necessary.

  Other information: 

  • To access or replace the fuses, see Fusebox, passenger compartment, replacing
  • Connect the breakout box.
  • For information about signals, see Signal specification, brake control module (BCM) with STC/ TRACS and Signal specification, brake control module (BCM) with DSTC (dynamic stability and traction control)
  • For information about checking wiring and terminals see Checking wiring and terminals .
  Fig 2: Breakout Box

  Courtesy of VOLVO CARS OF NORTH AMERICA.
  Fig 3: Identifying Ohm Meter

  Courtesy of VOLVO CARS OF NORTH AMERICA.
  Fig 4: ABS Control Module

  Courtesy of VOLVO CARS OF NORTH AMERICA.

Was a fault detected? 

• YES 

  Refer to Checking the brake control module (BCM) 

• NO 

  Refer to Checking communication with the brake control module (BCM)