Open-circuit, permanent faults

Fig 1: Checking For Open Circuit

Courtesy of VOLVO CARS OF NORTH AMERICA.

An open-circuit in a cable is indicated by a loss of one or more functions.

Chafed and broken cables or terminals that have come loose are common causes of faults in electrical systems.

Checks: 

• Disconnect the connectors at both ends of the cable.

Connect an ohmmeter between the ends of the cable.

The ohmmeter should read approximately 0 Ω if there is no open-circuit in the cable.

Fig 2: Identifying Control Module Installation

Courtesy of VOLVO CARS OF NORTH AMERICA.

Always check the control module and control module box connectors to ensure that their pins and sockets are not bent or damaged, as this can cause faults.

Check pins and terminals particularly for this fault. See Check terminals visually .