Interior fan stays on high on 2004 Chrysler Pacifica

Interior cabin fan alway remains on high. The fan speed control has no effect. Powering off the climate control has no effect.

by in Fall Creek, OR on February 01, 2009
5 answers 3 comments
ANSWER by on February 01, 2009
The power module for your Auto Temp Fan Control is defective. The blower motor power module allows the microprocessor-based automatic temperature control (ATC) A/C-heater control to calculate and provide infinitely variable blower motor speeds based upon ATC programming which uses a pulse width modulated (PWM) circuit strategy. The Blower Motor Power Module is easily replaced in less than 1 hour.
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COMMENT by on July 29, 2010
have replaced the blower motor resister once it solved the problem then 7 months later it reared its ugly head again replaced same part no fix this time fortunatley dealer took part back! What else could it be please help very irritating!!!
ANSWER by on March 05, 2009
I HAVE A 2004 PACIFICA WITH THE SAME PROBLEM. THE BLOWER MOTOR RESISTOR WAS BAD. IT IS LOCATED BEHIND THE GLOVE BOX UNDER THE DASH. THERE IS ALSO A FILTER UNDER THE DASH I FOUND FOR THE AIR COMING INTO THE CAR. THIS HAS NOTHING TO DO WITH THE FAN RUNNING BUT MINE WAS DIRTY. THR PART IS EASY TO CHANGE AND COST LESS THAN 20 DOLLARS.
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COMMENT by on June 11, 2010
Does the dash need to be removed to get to this part?
ANSWER by on May 13, 2010
well i jsut had that problem in my shop ,,and i had to replace the control unit on the dash ,,then blower motor resistor(module).the blower motor module was 254.00 dealer item only..and the control unit was a lil harder to find ,,the dealer told me they are not making them anymore so i had to find one in a salvage yard i tried to replace resistor first but it didnt change a thing...
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ANSWER by on January 18, 2011
I had the same problem and went through the same steps, but it ended up being my ignition switch! Amazing how one thing can effect everything else!!
COMMENT by on March 20, 2013
Blower never shuts off. Changed filter for A/C intake. R/R 3 resistors . Checked all fuses. Tore apart the HVAC control panel and tested all wires. All wires tested out fine. Shut off control panel and blower still runs even with the car off sometimes. Noticed my ignition switch is acting funny now too. When the off button is applied the blower goes to either A/C or re-circulate. So just how many fuses does a HVAC control panel have ? I can't control speed of blower motor nor can I find a short in the wires , OMG someone help me . I live on 416 bucks a month with 15 yr old twins and not in good health, live in Wisconsin and need this to work ! Can a simple fix of a ignition switch actually be the problem ?
ANSWER by on June 11, 2015
Front blower power module-located behind glove box-could have a shorted output transistor. Can be replaced with N channel Mosfet = HUF75345P3-ND TO-220AB case 55volt 75A rating. Cost about $3.00 at Digi-Key. Takes some heat to unsolder the old transistor.