Checking the proper functioning of the preheating system (Opel Corsa B)

1. Check the heater control module fuse. The fuse is located in the fuse box, in the engine compartment, near the left shock absorber strut.

2. Disconnect the temperature relay wiring connector.

Temperature relay connector



3. Connect a voltmeter between the center terminal of the glow plug and ground.

Connecting a voltmeter



4. Turn the ignition key to position II. The glow plug indicator lamp should light for about 3.5 seconds and the voltmeter should show voltage for about 7 seconds. If not, check the glow plug relay or supply wires in the electrical diagram.

5. Connect the temperature relay connector.