1996 Buick Lesabre Heat

WHITEBAYER

MEMBER
1996 BUICK LESABRE
6 CYL
FWD
AUTOMATIC
89,000 MILES

When the heat is turned on there is heat from the ducts on the driver siide but cool air on the passenger side. The vehicle has the Dual Comfor Temp Climate Control (option). When the temperature is set at 21 for example and the Auto control is pushed the 21 will blink on and off, and auto will only remain on when the air flow is to the floor only. Without using auto the air flow will continue regardless of the setting but it is hot to the left and cold to the right?

1 Reply

MERLIN2021

MECHANIC
17,250 POSTS

Only a Tech I scantool can read the trouble codes, so a trip to the dealer may be needed. But it sounds like this is your problem.
DTC 41 Passenger Air Mix Valve Circuit Open Or Shorted, Or Not Calibrated 1. Perform NORMAL SYSTEM RESPONSE TEST. Disconnect passenger air mix valve actuator connector, located on programmer. Turn ignition switch to RUN position. Using voltmeter, measure voltage between passenger air mix valve actuator harness connector terminals No. 8 (White wire) and No. 10 (White wire). If voltage is approximately 5 volts, go to step 3). If voltage is not approximately 5 volts, go to next step. 2. Inspect passenger air mix valve actuator, associated wiring, and harness connector for loose or poor connections between actuator and programmer. Repair as necessary. If no problems are found, replace programmer. 3. Using voltmeter, measure voltage between passenger air mix valve actuator harness connector terminals No. 8 (White wire) and No. 9 (White wire). If 4 volts or more is present, go to next step. If voltage is less than 4 volts, inspect wiring and connectors between passenger air mix valve actuator and programmer for loose or poor connections. Repair as necessary. If no problems are found, replace programmer. 4. Inspect passenger air mix valve for broken or binding components, or improper adjustment. See AIR MIX VALVE under ADJUSTMENTS. Repair as necessary. If no problems are found, replace passenger air mix valve actuator.
You can try this to adjust it. AIR MIX VALVE 1. Remove glove box. Start engine. Set temperature control to 90 °F (32 °C). Set passenger control panel to full WARM position. If ambient temperature is greater than 90 °F (32 °C), disconnect in-vehicle temperature sensor. Allow at least 45 seconds for programmer output cranks to reach full heating position. 2. Gently pull driver air mix valve crank toward programmer until valve contacts stop. Insert threaded portion of link into slot on plastic pin on driver air mix valve crank. 3. Gently pull passenger air mix valve crank toward actuator until valve contacts stop. Insert threaded portion of link into slot on plastic pin on passenger air mix valve crank. See Fig. 1 .