Circuit test

The fault is caused by an open-circuit in one of the relay circuits in the lock unit. To determine in which circuit the fault is:

Disconnect the connector at the lock unit.

Check the connectors for contact resistance and oxidation.

Measure the resistance between terminals #2 and #4 on the cable connector.

Other information 

• To access and replace the lock unit, see Lock mechanism, tailgate, replacing
• Checking wiring and terminals .

Fig 1: Identifying Connector Terminals

Courtesy of VOLVO CARS OF NORTH AMERICA.

Fig 2: Identifying Ohmmeter

Courtesy of VOLVO CARS OF NORTH AMERICA.

The ohmmeter should read 0 ohm. 

• OK 

  Refer to Checking ground lead 

• NOT OK 

  Refer to Circuit test continued