First, we'll test the BCM. It is located below the passenger's side maxifuse box under the hood. You can also trace the wire loom from the blower motor to the BCM. There are two larger gauge wires that are the output to the blower motor. With the fan set to the highest setting, the output should be equal to battery voltage. If it is then check the connection at the blower motor by wiggling and/or disconnecting the connector. If the blower still doesn't operate after this then it is faulty.
If the BCM output does not show battery voltage when the fan is set to the highest setting, check the control wire (gray on a '93). This wire should show about 8 volts. If it does then the BCM is faulty, if not there is a problem with the HVAC programmer or the control wire.
For the air mix actuator, you can inspect the operation by removing the inner glove box compartment. This is what you'll see:
With a flashlight you can see the end of the air mix rod (silver threaded part) and the air mix door lever (yellowish plastic piece). Adjust the temp setting from full hot to full cold while observing the action of the ros and lever. It will have about a 90* swing and move smoothly without stopping providing you do not pause while adjusting the temp. If it does not move smoothly or at all then that is the problem.
The service manuals indicate to remove the dash in order to change the actuator but several people have been sucessfull in replacing by removing the heater core cover. the actuator actually mounts atop the cover but it can be pretty tight to get at.
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10-13-2005, 09:43 PM
