I have a '97 ford escort. Every now and then the radiator cooling fan and A/C compressor kick off at exactly the same time and the engine overheats, sometimes to the point where I have to stop and let the engine rest a while before I start it up and go again. It seems to do it in warm weather more than in cold weather. (Or maybe it does do it in cool weather, but I just don’t notice the engine overheating.)
Anyway I’ve had this one relay replaced several times. The mechanic citing that the relay was the cause, but the problem persists. I just had the problem again and took it to a new mechanic and he said the same relay was the problem again!! I decided not to go ahead and change it again as this relay plus labor is about $150.00. Can anyone help me pinpoint the cause of the real problem? I have a wedding to go to in early July and need to have this cart in tip-top shape for this trip, because it is a 400 mile trip.
I cant really help except to say that you need to find out why the relay keeps failing. Some parts are badly designed, but sometimes there is a wiring problem that will cause a part to fail repeatedly. Test the resistance to the ground lead from the relay and see if it is high, as that would indicate a poor circuit, which could cause the relay to fail.
ignoramus9 is right. The relay might be bad - again - but that is the thing about a failed relay. Sometimes they do just fail. But very often the relay is killed by a wiring fault. This seems almost certain in your case. Replacing the relay is sort of like taking pain killers for a broken leg - it might cover up the real problem for a little while but fails to actually treat it.
Someone has to check out the whole circuit.