I have an Audi A4 1.9 tdi quattro with the AVF engine. Noticed that even after a long period on tickover(temp 90+) my electric cooling fan doesn't kick in. I have the electric only cooling fan(1) with the control unit on top of radiator. Have checked fuses(ok). I have run fused leads directly to fan and it works, so assuming there is a problem with control circuit.
Also cannot turn on AC as low on gas. Is there a test procedure to test only the radiator fan operation?
Have found various test procedures for passat/golf but none for the A4.