When we turn the fan speed to setting number 4, the A/C light turns off and the fan shuts off. It acts identically as if we had turned the knob to off.Troubleshooting:
- Mechanic friend of the family replaced a resistor. Didn't fix problem.
- Pulled console panel off to access the C1 connector and associated wiring (see #03-01-37-003 bulletin below). Didn't fix problem.
- With console panel off, did the following:
- Inspected fan speed selector switch. Found some weird build up around the base of one of the prongs. Opened up the switch and found metal tab associated with that prong looked like a short had occurred. Nothing was charred, per se, but it clearly didn't look like any of the other prongs or metal tabs. See the pictures in this photo album:
- With the ignition turned to on (with the engine not running), I used a wire to create a closed circuit that the switch normally would. The switch has 5 wires. "Shorting" several possible combinations resulted in 4 distinct fan speeds. I used this testing to verify the fan motor was fine and the "upstream" controller boards were fine.
A/C and Heater Blower Speed Switch Was Bad. GM part number 15803801. Dealer price is about $97 but a couple Google searches found it for $55.Steps Involved:
- Remove the center console:
- Remove the gear shift console "collar" that rings the gear shift by gently prying up from the cup holder end until the snaps release. There are no screws securing this collar that holds the power window switches and lighter/charger.
- Unscrew the console storage recess from the center console (directly beneath the A/C control panel. There are 4 screws.
- Gently pry the center console panel from the dash board. Roughly, it has snap connectors in 4 locations, 2 on each side, around the four points that contact the vertical part of the dash. Note: The top portion of the center console has tabs that slide into the top of the dashboard. After releasing the console from the center dash, you must slowly pull the console forward to free the tabs.
- Disconnect the electrical connections on the back side of the center console. I didn't take notes of these but there are about 4 of them (2 for A/C, one for the emergency flashers, one for something else). There is also a cable that connection to the temperature selector that does not have to be removed.
- Remove the A/C fan blower switch by pressing inward on the 3 plastic prongs holding it to the A/C control board. Don't force this, but it will take a little strength to hold all 3 prongs and wiggle the switch out.
- Insert new switch and reconnect everything back up.
Found this link in my Googling, specifically, it provides the text and graphics for a Saturn Technical Service Bulletin (#03-01-37-003):
"Inoperative HVAC Rear Defrost Recirc, or Air Condition (AC) Mode Switches and/or Reduced or No Airflow from Vents (Calibrate HVAC Module Controller and/or Inspect C1 HVAC Controller Connector) - (Dec 9, 2003)"