I have a 97 diesel. I am looking for the relay for the heater fan motor. I have heat in the rear but the fan does not work in the front. Nothing in the box under the hood is marked or the box under the dash. Heat will come through after a while but no fan. I bought a new one from the parts house, but it looks like it must be mounted by itself somewhere. The switch on the dash for the fan is new and the selector switch is new. The hot/cold dial is older. No power to the fan motor. Thanks for any help.

 

I have never worked on a 1997 E-series diesel doing heater work, so I can't give a positive answer. Since you have not had a response, let me give some good general advice.

No Ford I know of uses a relay for the heater fan motors. Both the front and rear are powered from one fuse. Since the rear works, the fuse must be good. What you should do is :

1) make sure you have power to the 1st switch by testing from its connector
2) if power in is good, probe the back with the switch on and make sure you have power out.
3) if good, go to the connector for the heater blower and see if it is getting current.

4) If you have A/C you should have a resistor pack somewhere. This is usually looks like a square patch with four bolts holding it on. You can find it by tracing your wires from your fan switch to it.

 

With these newer electronic marvels nothing is simple anymore.

Closest wiring diagrams I have are for a 97 Explorer, and it shows a blower motor relay and a high speed blower relay. Both are in the underhood auxiliary relay box number 2.

A wiring diagram would be most helpful.

 

I only found one box in the engine compartment with fuses and relays. All the fuses were good. Nothing was marked, so I switched the relays one at a time. The last one I tried was partly melted. I put in a new one and bingo I have a fan.
Thanks very much for the replies.

 

Good deal, glad to hear it's fixed.