Pinpoint Test C: Climate Control System Functional Test

• Using a scan tool, perform PCM and BCM self-tests.

Are any climate control related Diagnostic Trouble Codes (DTCs) present? 

1. Yes:  Refer to POWERTRAIN CONTROL MODULE (PCM) DTC CHART  .
2. No:  GO to C2

• Ignition ON.
• Using a scan tool, perform BCM self-test.

Are any climate control related Diagnostic Trouble Codes (DTCs) present? 

1. Yes:  Refer to BODY CONTROL MODULE (BCM) DTC CHART  .
2. No:  GO to C3

• Ignition ON.
• Select register mode.
• Observe blower motor operation and select each blower motor speed.

Does the blower motor operate in all selections and change speed in each? 

1. Yes:  GO to C4
2. No:  If the blower motor does not operate in any setting, GO to Pinpoint Test K 

   If the blower motor does not correctly change speeds or turn off, GO to Pinpoint Test L 

• For correct airflow descriptions

  REFER to: Climate Control System - Vehicles With: Electronic Manual Temperature Control (EMTC) - System Operation and Component Description  .

• Select the highest blower motor setting.
• While observing the airflow, select each of the airflow positions (register, register/footwell, footwell, footwell/defrost, defrost).

Is the airflow directed to the correct outlets? 

1. Yes:  GO to C5
2. No:  GO to Pinpoint Test E 

• Select register mode.
• Select the highest blower motor setting.
• Observe airflow noise.
• Press the recirculated air button (indicator on).

Does the airflow noise increase when the recirculated air mode is selected (indicator on)? 

1. Yes:  GO to C6
2. No:  GO to Pinpoint Test D 

• Start the vehicle and allow it to reach normal operating temperature.
• Make sure the A/C indicator is off. Press the button once if it is on.
• Select register mode.
• Change the temperature setting from the coldest to the warmest.

Does the temperature vary between significantly warmer than the ambient air temperature to ambient air temperature or cooler? 

1. Yes:  GO to C7
2. No:  If the temperature does not get significantly warmer, GO to Pinpoint Test F 

   If the temperature does not change significantly, GO to Pinpoint Test J 

• Set the temperature setting halfway between the coldest and warmest.
• Visually inspect A/C compressor clutch.

Is the A/C compressor clutch engaged? 

1. Yes:  GO to Pinpoint Test I 
2. No:  GO to C8

• Make sure the ambient air temperature is above 6 C (43 F).
• Change the temperature setting to coldest (MAX A/C).
• Press the A/C button if the indicator is not on.

Does the A/C clutch engage and cycle on/off when the A/C indicator is on? 

1. Yes:  GO to C9
2. No:  If the A/C clutch engages but never cycles on/off, GO to Pinpoint Test H 

   If the A/C clutch never turns on, GO to Pinpoint Test G 

• Change the temperature setting to coldest (MAX A/C).
• Press the A/C button if the indicator is not on.

Does the A/C compressor clutch engage and cycle on/off when the A/C indicator is on? 

1. Yes:  The system is operating correctly.
2. No:  REFER to: Refrigerant System Tests  .