QuestionProblem: radiator cooling fan w/not come on normally. operates ok if a/c switch is placed in the "Norm A/C " position. I have replaced the following prior to this problem:
Water pump,thermostat,hoses,raditor,cooling fan, both tempature switch's plus the 28 pin control box on the front core support. All was working normal for several months, then all of a sudden, the motor got a little hot, which I checked promptly and found the fan was not coming on but will if the a/c switch is in the a/c position. I have relaced both temp control swiches again, but it does not fix the problem.Also had a new heater core installed Dec 2002. Any suggestions outside of taking it to the ford place?
AnswerThe cooling fan turns on when the A/C is on and bypasses all of the temperature controls. This is normal. It sounds like you've replaced everything. Cooling fans do come on at a higher temperature than most people would think. If the temperature gauge has not gone to the HIGH side of normal, then I would allow the engine to run (without letting it overheat).
According to the '96 Service Manual -- that's as far back as I have available -- with the A/C off, the constant control relay module will turn the fan on low at 216 degrees and off at 212, and on high at 228 and return to low at 222. If the cooling fan doesn't turn on at these temperatures, considering you've replaced the CCRM and temperature sensors, a wiring problem is likely.
Hope this helps,
Dave
