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well I finally get a day off work tomorrow and thought I would try to fix my heater problem. How do you test the blower motor and what other things should I check? The air mix actuator seems to work fine. It moves from side to side smoothly. Any other ideas? Thanks guys!

For the blower motor you can disconnect the power connector and apply 12 VDC directly do the motor. If it is a bad motor, you can find them at just about any junk yard. They're easy to remove/install.

It could be just a relay that is bad causing the motor not to function too. On your year I think that relay is under the hood.

I've found that the problem is usually either a relay, faulty connection, or the motor.

Have you purchased the Haynes or Chilton's book for the car? These books are a great resource and I strongly recommend them. They aren't all inclusive, but they will get you started in the right directions.

- Phibes

Hold up.

There are two different types of systems in play on our cars. Those with ECC, and those that are just the knob. Both are different in many ways...and how power is delivered to the blower motor is one of them.

In the standard setup, you have a a relay and a resistor board that resides on top of the blower box, hidden by the fuse and relay center. Start your troubleshooting at the fuse level. If all that is good, grab a DVM (or a 12v light), disconnect your motor and put your tester on the motor leads. Voltage level (or lamp brightness, if you use that instead) will depend on your speed setting. If you get NOTHING on any setting, your issue lies with power delivery after the fuse. If you get nothing except high-speed, your relay works just fine (as the relay only works on high), and its your resistor board that is fried. If everything works, double check your connector going to the blower motor. On my '97, I found the ground wire completly broke from the terminal inside the connector. It made contact in one direction, lost it in another.

In the ECC setup, there is no relay...all is controlled by the blower control module (BCC), which resides where the resistor board would if it were the standard setup. These have two known modes of failure...either failed on, set to high, or nothing at all. Possibly a third mode of failure is correct voltage but low amperage...been seeing some of that lately too, and thats not mentioned at all in the FSMs.

Phibes wrote:Have you purchased the Haynes or Chilton's book for the car? These books are a great resource and I strongly recommend them. They aren't all inclusive, but they will get you started in the right directions.

- Phibes

I personally prefer factory service manuals over Chilton's/Haynes. Those books are designed off of taking a car apart and putting it back together. FSM's are designed with single problems, and diagnosing them.

Very few people actually need a FSM over a Haynes or Chiltons. 99% of what most people will do will be included in those books.

I have purchased a Haynes book for every vehicle I have ever owned and only once did I ever need a FSM and that was for diagnosing the no run / no start problem on my '93 SSEi last summer