A/C Problem
freels1975
05-10-2005, 07:47 PM
I am having a problem with my A/C. It still blows hot and cold. But it only blows on High. I was looking at my Haynes Electrical system and was thinking it was the Front Blower Motor Resistor Block. But I really don't know. Any and all help would be great. My car is a 2000 Chrylser T&C Limited. Thanks!
GTP Dad
05-11-2005, 06:45 AM
I believe your analysis of the problem is correct. The resistor control voltage for the fan at lower speeds. Once it goes bad the fan will only work on high. If you replace it the problem should be resolved.
yogi_123rd
05-11-2005, 05:31 PM
There MAY be a second cause for this type problem other than the blower motor relay. I had a simular problem on a GM model car and the cause was not the expected blower resistor but a relay.
In your Hayes manual, locate the wiring diagram for the blower motor circuit. See if the slow speed circuit has the output from the blower motor resistor going as input to a relay and then to the blower motor. If so, the relay will act as a switch. Energizing the relay gets high speed (full battery voltage) and the default (not energized) uses the voltage output from the low speed circuit going thru the resistor. If the blower speed circuit has a relay as described, then your problem may be with the relay being bad instead of the blower motor resistor.
In my case, the relay had bad/burnt contacts. The blower motor would only work on high speed because the relay switched the source voltage from the bad contact default path to a good contact max voltage path.
In your Hayes manual, locate the wiring diagram for the blower motor circuit. See if the slow speed circuit has the output from the blower motor resistor going as input to a relay and then to the blower motor. If so, the relay will act as a switch. Energizing the relay gets high speed (full battery voltage) and the default (not energized) uses the voltage output from the low speed circuit going thru the resistor. If the blower speed circuit has a relay as described, then your problem may be with the relay being bad instead of the blower motor resistor.
In my case, the relay had bad/burnt contacts. The blower motor would only work on high speed because the relay switched the source voltage from the bad contact default path to a good contact max voltage path.
freels1975
06-12-2005, 12:47 AM
I also need to know if anyone has the part number and the location of where the resistor block is. I an thinking it's behind the glove box, but then again it may be in under the hood. Any and all help would be much ablidged. Also, if there is any website dealing with this that anyone knows about, that would help also. Thanks!
caravandrvr
06-12-2005, 06:26 AM
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The resistor is probably located on the passenger side engine compartment firewall. Open the hood, stand in front of the passenger side headlight and look straight back. My guess is that you might need the plug as well if it looks as bad as this one:
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http://www.geocities.com/caravandrvr/blowerresistor02.JPG
The resistor is probably located on the passenger side engine compartment firewall. Open the hood, stand in front of the passenger side headlight and look straight back. My guess is that you might need the plug as well if it looks as bad as this one:
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http://www.geocities.com/caravandrvr/blowerresistor02.JPG
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