Contour Enthusiasts Group Archives Forums General Troubleshooting ac/heater...im going crazy!!!!!

guys this is the second post..sorry but i am going crazy..I checked my fuses (not blown), blower motor works(tested it) changed realys and bought a new resistor and speed control potentiometer and the damn things still does not work Help...what can it be???? I have worked on it for the last four days and I am fed up. What can it be? . This last summer i went to my girlfriends house full blast with a/c left and tried to turn it on and just like that nothing was working not even the heater??? I am stumped on this one....desperatley in TX ....

As I understand it, you're saying:

1 Fuses 1, 3, 23, and 37 are good.
2 The Ignition relay and the Blower relay are good.
3 The Blower speed switch is good.
4 The Blower motor is good.
5 The Resistor pack is good.


This leaves:

6 Blower Mode switch (off,panel,defrost...)
7 Grounds and other wiring.

If the mode switch is bad the blower relay will never turn on.

when you say blower mode switch you mean the switch with panel,ac,defrost etc. right? And would you know what ground and where it would be located. Any suggestion will be taken. Thanks

I actually took a look at the switch and it looked ok and didnt smell fried.

You need a test light or meter.

The Blower Mode switch has two contacts, one to turn on the Blower Relay and one to turn on the A/C compressor. When in any position but off the Blower Relay should be on. The Blower relay is connected to the Resistor Pack and then to the Blower Motor. The Blower Speed switch only bypasses part of the Resistor Pack to provive higher speeds than the low speed resistor.

Check for 12v starting at the Blower Mode switch, then the Resistor Pack, then the Blower Motor. If there is nothing on the Blower Mode switch, check the Ignition relay. If there is nothing on the Resistor Pack, check the Blower relay.

The wire that goes to your blower motor has the following colors:

Black/Red for negative (GND) and Purple/Black for positive.


Placing the fan switch to high bypasses the resistor pack altogether. The resistor pack and the fan speed switch is part of the negative circuit.

Remove the fan.
To test if this circuit is working place the fan switch on at high speed with ignition on. Turn the other switch to defrost.

With a voltmeter set to volts DC place the black probe on the plug contact of the black/red wire. Place the red probe to 12V, use you cigerette lighter for the 12V source. You should see 12Volts.

Another option is to set your meter to ohms and place the red probe to the car chassis and there should very little resistance.

This checks that your wiring to the fan speed switch is ok.


Now we have to check the wiring of the purple/black wire.
With the same setup as above place the red probe to the purple black wire on the connector. Now place the black probe to the car chassis and you should read 12V.

This checks tha positive circuit.

Find out which circuit is bad, that helps us troubleshoot
your problem.

I have a drawing I can email to you if you need it.

Advise us on your results.

Carefull with the wire colors. My blower motor wires are black and white/black.

Good advice.
Black would be negative and black/white is positive.

There are only two wires to the blower motor, and you can't do any damage with the above tests.

The reason for testing the positive circuit and the negative circuit seperatly is that they have different functions.

The negative circuit has the fan speed control stuff, aka the famous resistor pack and the fan speed switch.

The positive circuit is where all the fuses and relays are assocoated with.

Testing each wire will isolate what we are dealing with.

I think there might have been a recall on the blower moter awhile back check with your local dealer to see, they have had some recalls on a few switches for all years

Hey guys..jborge thanks for the advise..I will get a volt/ohm meter tommorow and I will let you now what the out come is. This is greatly apreciated.