1989 blower speed problem
#1
1989 blower speed problem
Hi everyone,
I have an '89. The heater/ac blower only works in the high speed setting. I would like to know if anyone can help me find the faulty part. I believe the fan switch itself is working correctly. I tested it and the contacts seem to be working. I haven't found the blower, but it looks like it is under the glove box area. The blower is working anyway. I haven't found an pics of what I am looking for. Can anyone help ?
Thanks,
Glenn
I have an '89. The heater/ac blower only works in the high speed setting. I would like to know if anyone can help me find the faulty part. I believe the fan switch itself is working correctly. I tested it and the contacts seem to be working. I haven't found the blower, but it looks like it is under the glove box area. The blower is working anyway. I haven't found an pics of what I am looking for. Can anyone help ?
Thanks,
Glenn
Last edited by gironha; 03-16-2017 at 05:52 PM. Reason: More info
#3
Welcome to the site...
Yes,, in the blower case. The default is high fan speed. When the lower speeds are selected/commanded with the fan switch, the voltage remains the same, grounding resistance changes within the resistors coils selected by the fan switch. When you pull it out, most often the thermal protection ( looks like a bullet shaped diode stretched between the coils) has an open. If you take a test lead and bridge the thermal unit where it connects to the resister unit,, all fan speeds should then work. Thermal protection is needed, so if it's open, a simple replacement resistor is the fix...
Yes,, in the blower case. The default is high fan speed. When the lower speeds are selected/commanded with the fan switch, the voltage remains the same, grounding resistance changes within the resistors coils selected by the fan switch. When you pull it out, most often the thermal protection ( looks like a bullet shaped diode stretched between the coils) has an open. If you take a test lead and bridge the thermal unit where it connects to the resister unit,, all fan speeds should then work. Thermal protection is needed, so if it's open, a simple replacement resistor is the fix...
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