1988 Town Car Heater / AC Stops

[Goodsport45]

Last week the AC fan stopped without warning and then came back when I shut it off and then turned it back on. Happened again yesterday. I changed the fan about 5 years ago and when it runs, the system is fine. I know intermittent problems are sometimes hard to find. Is there a relay or switch under the hood that I might change or can someone recommend something else? (Those switches are cheap and easy to replace.) Electronics is not my strong suit. Thanks for your help.

[TonyC]

Well, granted, by 1988 there were a lot more electronics applications in use, so if the problem is somewhere in there I cannot really give advice. But on older cars, there was a plate with a cluster of resistor coil wires which was the primary switcher for fan speeds. If one resistor wire coil fried and broke, that would cause the symptoms you are now having. If the '80s Box Cars still used resistors, then the first thing I'd recommend checking is the condition of the wire coils on that plate...and while at it, the condition of the wiring harness that plugs into that plate.

OR...if your system has a manual selector switch for fan speed, check it as well. I remember the fan-speed switch on my old '79 Electra being the cause for failure of the highest speed setting for that system's fan.

---Tony

[action]

Here is a wiring diagram.

No resistors. Different fan speed is changed by blower speed controller base on input from the EATC module.
Intermittent operation? Look for a poor/loose connections. That would be the typical issue.

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If you are going to do your own electrical repairs (especially is that isn't your strong suit) don't do this blind!!
Even pro techs don't go into a repair like this with out the tools and help, why would you?
Best ten bucks you will spend to fix your car.
https://www.ebay.com/itm/361948861391?h ... SwpP9Y6Em1

Shows the wiring, location of parts and connectors, wire color, circuit number. A detailed may of the wiring of your vehicle.

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