vze2jshn

Trying to locate a/c condenser fan temp switch. Also wondering if the switch can fail causing a short that blows the fan fuse?

griffiths

Things that can cause the primary AC fuse, position #2, to blow:

In no particular order,

1) Evaporator Fan Motor
2) Evap Fan Speed Resistor Unit
3) Evap Fan Speed Switch
4) The "Relay AC"
5) and, a 'short'

vze2jshn

Thanks, but my car is a 1978 so my wsm wiring diagram is different (no thermostat,resistor pack) as far as I can see.Wondering where the temp/pressure switches are located for the condenser fan. Is one at the bottom of the radiator and the other on the receiver drier? I am trying to track down short that blows just the condenser fan fuse. AC compressor comes on and blows cold so that fuse is not affected.

griffiths

The schematic is for the factory Behr system.

Some early cars, going back, had a "temperature sensor" screwed into a blind hole on the receiver drier in the LH front fender that would
turn off the compressor.

If you mean the front condenser blower motor, it is driven by an AC relay and the relay 'makes' when the thermostat contacts make.

"Radiator" ... let's use that term for an engine coolant system. Here, let's use terms 'condenser' or 'evaporator;
Condenser is under the engine deck lid and if your car has the option there is one under the front nose.

The front condenser never had a 'fuse' until the 88-89 time frame.
Some people added an inline fuse next to the front condenser blower motor.
Send a picture of the the location of your fuse.
Normally the added front condenser fuse, 7.5 amp, blows when the front condenser motor draws
too many amps or shorts.

The Forgotten On

The temp sensors that control that fan are in the radiator and the receiver drier.

The rad switch is in the bottom right corner (facing the car from the front).

The temp sensor in the drier is on top and has a short pigtail harness that connects 2 spade connectors.

These 2 things control the fan independent of each other and will cause the fan to run if either one is tripped.