Checking the thermal time relay (VW Passat B4)

Disconnect the high-voltage wire from the ignition distributor and connect it to the body ground via an extension cord. Remove the thermal time relay from the engine and immerse its sensitive element in coolant with a temperature below 30°C. Connect the thermal time relay connector and connect the relay to the ground. Disconnect the starting injector connector and connect the test lamp wires to the injector block terminals (fig. 2-191).



Turn the engine crankshaft for approximately 10 seconds. The indicator lamp should light for 1-8 seconds.

Note: If the test is performed at a higher temperature than that marked on the thermal time relay housing, the control lamp will not light.