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Home >> GMC >> 1999 >> Safari Van AWD V6-4.3L VIN W >> Repair and Diagnosis >> Heating and Air Conditioning >> Control Assembly >> Description and Operation >> HVAC System - Manual >> Mode Controls
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Mode Controls

Temperature Control Motor Circuit Description


The temperature control motor is powered from the CKT 141 (BRN) cavity 10. The rotation of the temperature control motor moves a wiper contact along the resistance body. The rotation varies the voltage which is passed through the CKT 733 (LT BLU) to the temperature control motor. The temperature control motor senses the voltage provided at CKT 733 (LT BLU) cavity 8. Rotating the temperature control knob to one direction signals the temperature control module to command the motor to rotate proportionally to the correct voltage. Full voltage is a full rotation in one direction. A very low voltage is a full rotation in the opposite direction.
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