AC Fan speed problem

[modelt609]

87 Turbo The AC fan will only work on low and medium speeds-changed the resistor and the fan relay and still same problem- any thoughts on what next- could it be a switch problem and which part do I change next?

There are complete AC /Temp control units on ebay but you never know their condition. Thanks for the reply
Gene

 

[salvageV6]

There is a connector usually buried in the passenger fenderwell area near the power antenna.

It has a fat red wire that provides power to the silver high speed relay mounted near the blower fan.

Make sure the fat red wire on the blowerr fan has +12 on it at all times since the connection goes down the fender to the fusible links at the starter.

If you have power on that wire it's probably a bad relay but that is rare.

Usually at that connector the connection corrodes and loses contact.

Wiggling it may get it to work or you can just cut both and splice the wires together, but remember they are LIVE to the battery, so disconnect the battery, if you are going to do a by-pass splice.

 

[modelt609]

87 Turbo The AC fan will only work on low and medium speeds-changed the resistor and the fan relay and still same problem- any thoughts on what next- could it be a switch problem and which part do I change next?

There are complete AC /Temp control units on ebay but you never know their condition. Thanks for the reply
Gene

 

[modelt609]

Thanks,

most options are chasing parts again great information

 

[salvageV6]

See the fat red wire? Give it a wiggle.

The orange wire on the relay is the trigger signal from the fan speed switch, it should have +12 on it with the IGN KEY ON and fan speed switch on HIGH. If it does it's not the control head switch.

The fat red wire shown below also goes to the high speed relay and has +12 on it at ALL times direct from the fusible link A.

 

[josh young]

Id try some contact cleaner on the switch itself.