Checking Components And Wiring

Check the cable between the central electronic module (CEM) and the back-up (reversing) lamp switch. Check for an open-circuit. Check for a short-circuit to ground.

Take readings between:

Central electronic module (CEM) terminal #C34 (34) and back-up (reversing) lamp switch terminal #1 (3/10).

Measure the resistance between back-up (reversing) lamp switch terminals #1 and #2 with gears 1 to 5 engaged. The resistance must be high.

HINT: The back-up (reverse) gear switch should be open in all gear positions except back-up (reverse).

Remedy as necessary.

Other information

Fig 1: Identifying Connector C

Courtesy of VOLVO CARS CORPORATION

Fig 2: Identifying Light Switch Module (LSM)

Courtesy of VOLVO CARS CORPORATION

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Refer to VERIFICATION

Check central electronic module (CEM) connector C. Check for contact resistance and oxidation. Check for damage in particular.

Check the connector on the back-up (reversing) lamp switch. Check for contact resistance and oxidation. Check for damage in particular.

Check the cable between the central electronic module (CEM) and the back-up (reversing) lamp switch. Check for an open-circuit. Check for an intermittent short-circuit to ground.

Take readings between:

Central electronic module (CEM) terminal #C34 (34) and back-up (reversing) lamp switch terminal #1 (3/10).

Other information

Continue
Refer to VERIFICATION