LEMON Manuals: Even more car manuals for everyone
Home >> GMC >> 2003 >> Safari Van Cargo, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 968 (HVAC Systems - Manual) >> Diagnostic Information and Procedures >> Too Hot in Vehicle

Too Hot in Vehicle

WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
Too Hot in Vehicle

Step Action Yes No
Schematic Reference: HVAC Schematics 
Connector End View Reference:  HVAC Connector End Views  
DEFINITION: The temperature cannot be adjusted, or the cooling is insufficient during A/C operation.
1 Did you perform the HVAC Diagnostic System Check? Go to Step 2  Go to Diagnostic System Check - HVAC Systems - Manual 
2
IMPORTANT: If during this diagnostic procedure the HVAC control module is disconnected a recalibration of actuators must be performed to avoid misdiagnosis.
  1. Recalibrate actuators. Refer to Re-Calibrating Actuators .
  2. Turn ON the ignition, with the engine OFF.
  3. Observe the Diagnostic Trouble Code (DTC) List  in Heating and Air Conditioning.
Does the scan tool display any DTC B0414, B0424 or B3770?		 Go to Diagnostic Trouble Code (DTC) List  Go to Step 3 
3
  1. Turn ON the ignition, with the engine OFF.
  2. Place the blower motor switch in each speed position.
Does the blower motor operate in any of the speed positions?		 Go to Step 4  Go to Blower Motor Inoperative 
4 Does the blower motor operate at the desired speed? Go to Step 5  Go to Blower Motor Malfunction 
5
  1. Place the mode switch in the PANEL position.
  2. Place the recirculation switch in the ON position.
  3. Observe the recirculation door.
  4. Place the recirculation switch in the OFF position,
Does the recirculation door move from the recirculation position to the outside air position?		 Go to Step 6  Go to Air Recirculation Malfunction 
6 Does the customer concern occur when the A/C is OFF? Go to Step 9  Go to Step 7 
7
IMPORTANT: Ambient air temperature must be above 3°C (36°F).
  1. Start the engine.
  2. Place the blower motor switch in the maximum speed position.
  3. Place the A/C request switch in the ON position.
  4. Place temperature switch in the coldest position.
Does the A/C compressor operate?		 Go to Step 8  Go to HVAC Compressor Clutch Does Not Engage 
8 Perform the refrigerant system performance test. Refer to Air Conditioning (A/C) System Performance Test (without PHT)Air Conditioning (A/C) System Performance Test (with PHT) in Heating, Ventilation and Air Conditioning.
Did you find and correct the condition?		 Go to Step 12  Go to Step 9 
9
  1. Turn ON the ignition, with the engine OFF.
  2. With a scan tool, observe the Left Mix Door Actual and the Right Mix Door Actual parameters in the Heating and Air Conditioning Door Positions data list.
  3. Place the left and right air temperature switches from the coldest position to the warmest position.
Does the Left Mix Door Actual and the Right Mix Door Actual parameters counts change?		 System OK Go to Step 10 
10 Inspect for poor connections at the harness connector of the HVAC control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 12  Go to Step 11 
11 Replace the HVAC control module. Refer to HVAC Control Module Replacement .
Did you complete the replacement?		 Go to Step 12  -
12 Operate the system in order to verify the repair.
Did you correct the condition?		 System OK Go to Step 2 
scientia non olet · About LEMON Manuals