Intermittent fault

WARNING: This page is about a different car, the 2002 Volvo C70, 2001 Volvo C70, 2000 Volvo C70, 1999 Volvo C70, and 1998 Volvo C70. However, it is still accessible from the selected car via links, so may be relevant.

Check the control module and power unit connectors for contact resistance and oxidation according to Contact Resistance And Oxidation .
Check cable between control module #A14 and power unit for an intermittent short-circuit to supply voltage according to Short-Circuit To Supply Voltage, Intermittent Faults .
Check power supply to power unit #A4 for an intermittent open-circuit according to Open-Circuit, Intermittent Faults .
Check ground lead between power unit #B2 and ground terminal for an intermittent open-circuit according to Open-Circuit, Intermittent Faults .

The fault also could have been caused by the fan sticking, dirt etc.

Remedy as necessary.

Other information:

To access/replace the blower fan, refer to Replacing Blower Fan Motor .

Fig 1: Identifying 4-Pin Connector

Courtesy of VOLVO CARS OF NORTH AMERICA.

Fig 2: Identifying Ohmmeter

Courtesy of VOLVO CARS OF NORTH AMERICA.

Fig 3: Climate Control Module Connectors Terminals

Courtesy of VOLVO CARS OF NORTH AMERICA.

Fig 4: Identifying 1B And 2B Connector

Courtesy of VOLVO CARS OF NORTH AMERICA.

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