Checking the control unit

Check relay coil driver for a short circuit to voltage supply by checking the voltage on 2 in the relay socket.

For additional information regarding a short circuit to voltage supply, see Short-circuit to supply voltage. Permanent faults .

HINT: The voltage between 2 and ground must be approximately 0 V. 

Fig 1: Identifying Voltage Display

Courtesy of VOLVO CARS OF NORTH AMERICA.

Fig 2: Identifying Relays

Courtesy of VOLVO CARS OF NORTH AMERICA.

If the voltmeter indicates an incorrect value, the control unit should be replaced.

Additional information: 

• To access/replace the relay/fuse box in the boot, see Integrated relay/fusebox cargo compartment/Rear electronic module (REM), replacing .

Refer to Verification