Windscreen Wipers - Electrical Fault!

[Chegron]

Hi,

I am the proud owner of a 1990 Corolla and could use some assistance with a problem.

I have an intermittent fault with my windscreen wipers. The problem is with the electrics (I think!). Here is what I have tested/checked so far:

- Fuse behind driver side kick panel, this had blown one time, I replaced it and it has been OK since.

- Combination switch. In my frustration with the blessed windscreen wipers I managed to damage my combination switch. I have replaced this with one from the scrap yard.

- After purchasing a multimeter I tested the voltage at the wiper motor. This seems to be a normal (I think) 11.8 - 12 V when the wipers are working (and turned on) and 0V when not. This has lead me to believe the problem is not with the wiper motor.

- Checked the grounding point next to the wiper motor, continuity with negative terminal seems OK both when the wipers are working and when they are not. The grounding point is clean.

I own the Haynes manual for my vehicle but struggle somewhat understanding the electrical diagrams. If anyone can advise what other components to test (circuit breakers, relays etc..) it would be most appreciated.

I have tried removing the circuit breakers behind the left and right kick panels when the wipers were working. This had no effect (they remained working with the CB pulled). I also noticed that a large Relay behind the left kick panel was quite hot when the wipers were not working. Could this be an indication of the problem? - to be honest I don't even know if these components form part of the circuit I am trying to diagnose!

Help....please.....

Sincerely,
Charles.