Circuit/System Verification

WARNING: This page is about a different car, the 2019 Chevrolet Malibu. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

Check for bulletins before proceeding.

Ignition ON.
Verify every applicable scan tool switch parameter changes when pressing the appropriate switch on the A26 HVAC Controls.
- If any parameter does not change
  Replace the A26 HVAC Controls.
- Go to next step: If all parameters change
Verify the blower motor operates properly with the blower motor switch in each speed position.
- If the blower motor does not operate properly in each speed position
  Refer to DTC B0193 .
- Go to next step: If the blower motor operates properly in each speed position
Verify the HVAC doors listed below move when operating the appropriate control.
- Driver Temperature
- Passenger Temperature
- Mode
- Recirculation
- If any HVAC door does not move
  Refer to DTC B0223, B0228, B0233, B0408, B0413, B0418, B0423, B1395, or B374A .
- Go to next step: If all HVAC doors move
Install the appropriate Air Conditioning Service Center, ignition ON
Verify the high side pressure on the gauge is within 10% of the scan tool A/C High Side Pressure Sensor parameter.
- If the A/C High Side Pressure Sensor parameter is not within 10%
  Refer to DTC P0532 or P0533 .
- Go to next step: If the A/C High Side Pressure Sensor parameter is within 10%
Verify the A/C High Side Pressure Sensor parameter is between 269-2929 kPa (39-425 PSI).
- If the reading is not between 269-2929 kPa (39-425 PSI)
  Refer to Air Conditioning (A/C) System Performance Test
- Go to next step: If the reading is between 269-2929 kPa (39-425 PSI)
Verify the A/C Evaporator Temperature Sensor parameter is within 10% of actual conditions.
- If not within 10% of actual conditions
  Refer to DTC B3933 .
- Go to next step: If within 10% of actual conditions
Verify the scan tool parameters listed below are within 10% of actual conditions.
- Passenger Compartment Humidity
- Passenger Compartment Humidity Sensor Temperature
- Passenger Compartment Windshield Temperature
- If not within 10% of actual conditions
  Refer to DTC B018A, B048C, B048F, or B1395 .
- Go to next step: If within 10% of actual conditions
Verify the scan tool Sunload parameter changes while covering the B10B Ambient Light/Sunload Sensor with a shop towel or other suitable item.
- If the Sunload parameter does not change
  Refer to DTC B0163 or B0183 .
- Go to next step: If the Sunload parameter changes
Verify the actual inside air temperature, using a thermometer, is less than 3°C (5°F) difference from the scan tool Inside Passenger Compartment Air Temp. Sensor parameter.
- If greater than a 3°C (5°F) difference
  Refer to DTC B0163 or B0183 .
- Go to next step: If less than a 3°C (5°F) difference
Engine ON, A/C system ON.
Verify cool air flows from the ducts with the temperature control in the coldest position.
- If the air is not cool
1. Verify the Q2 A/C Compressor Clutch is engaged.
  - If the Q2 A/C Compressor Clutch is not engaged, refer to Air Conditioning Compressor Malfunction .
  - If the Q2 A/C Compressor Clutch is engaged, refer to Air Conditioning (A/C) System Performance Test , and DTC B393B .
- Go to next step: If the air is cool
Verify warm air flows from the ducts with the temperature control in the warmest position.
- If the air is not warm
  Refer to Heating Performance Diagnostic .
- Go to next step: If the air is warm
Engine OFF, ignition ON.
Verify the vehicle is equipped with RPO code KL9.
- If the vehicle is not equipped with RPO code KL9
  Refer to step 18.
- Go to next step: If the vehicle is equipped with RPO code KL9
Verify the G36 Auxiliary Heater Coolant Pump turns On and Off when commanded with a scan tool.
- If the G36 Auxiliary Heater Coolant Pump does not turn On and Off
  Refer to DTC B269A, B269C, or B269D .
- Go to next step: If the G36 Auxiliary Heater Coolant Pump does turn On and Off
Verify the vehicle is equipped with RPO code C32.
- If the vehicle is not equipped with RPO code C32
  Refer to step 20.
- Go to next step: If the vehicle is equipped with RPO code C32
Verify the E40 Electrical Auxiliary Heater is operating properly.
- If the E40 Electrical Auxiliary Heater is not operating properly
  Refer to DTC B048D
- Go to next step: If the E40 Electrical Auxiliary Heater is operating properly.
All OK.