Heater Motor on High Speed Only
Earlier the resistor was changed due to no fan at all worked for 4 months now fan motor blowing on high only. Could it be the switch or resistor or motor not sure can you help.
Usually if the fan only works on high, it is the resistor.
has new resistor still only works on high
has new resistor still only works on high fan
The most common cause here is a bad resistor, but since you are confident that isn't the problem, it is likely the switch. However, I did have a situation once in a dodge caravan. The fan motor itself was causing a voltage problem and ruining the resistors.
You can use a simple test light. Unplug the wire to the resistor. Should have a 5 or 6 prong plug. Turn the key to the run position. Probe each pin with the light as you change the setting on the switch. If it lights up at each setting that means it is working and the resistor is bad. If not, then the switch. If the resistor is new and not working, or if there are any melted connections, then the fan motor is the likely culprit.
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