Mechanics

COLD AIR IS ONLY COMING OUT OF PASSENGER SIDE VENTS

2000 Pontiac Grand Prix • 130,000 miles

I have a 2000 pontiac grand prix gtthat has cold air coming out of the passenger side but warmer air on the driver side. Basic temp controls, not digital or dual climate. What would cause this? Thanks in advance.
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Jake1755
August 18, 2012.




Vacuum leak, bad actuator or a binding vent door can cause that.


KHLow2008
Aug 18, 2012.
Thanks. How do I test those things?
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Tiny
Jake1755
Aug 18, 2012.
Sttart by checking for trouble codes.

RETRIEVING DIAGNOSTIC TROUBLE CODES

1. If a fault has occurred in a monitored circuit, the MAN symbol on right side of A/C-heater control unit display will flash during first 2 minutes of operation. To enter diagnostic mode, turn ignition on, then press both temperature knobs simultaneously for 5 seconds.

2. There are 2 display modes within self-diagnostics: diagnostic pointer and diagnostic value. By rotating driver's temperature knob, one detent in either direction, display is toggled between pointer and value.

3. Value displayed is decimal equivalent of Random Access Memory (RAM) contents. A "2" is formed using minus sign, and leading "1" in order to display values over 199. Diagnostic pointer mode is identified by a minus sign preceding pointer number. Pointer provides an index, identifying corresponding diagnostic value.

4. DTCs reside under diagnostic pointer 00. Pointer will be set to this position upon initial entry into self-diagnostics. If more than one DTC is present, they will be displayed sequentially at a rate of 2-second intervals per fault. Rotating passenger temperature knob will switch self-diagnostic pointers.

5. A wraparound feature is provided if pointer is continued past either end. Other data used by computer resides under different self-diagnostic pointers and may not be useful in diagnosing A/C-heater system. To exit diagnostics, press any mode button.


KHLow2008
Aug 18, 2012.
Looks like these instructions may be for dual climate control, mine is the basic 3 dial one. Thanks.


Tiny
Jake1755
Aug 18, 2012.
For the basic system you would need a scan tool to check. Our database does not have diagrams for the vents so I am not able to show you how.

Diagram shows an explode view of the heater housing and yu should be checking to see if any of the vents are stuck. Try turning to heater and back to A/C to see what happens.


KHLow2008
Aug 18, 2012.
Sorry, missed out the diagrams


KHLow2008
Aug 18, 2012.

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