Pinpoint Test M: HVAC Functions Verification
Climate Control System
Pinpoint Tests
Pinpoint Test M: HVAC Functions Verification
This pinpoint test is intended to diagnose the following:
- HVAC system
PINPOINT TEST M: HVAC FUNCTIONS VERIFICATION
NOTE: Diagnose any HVAC module DTCs before carrying out the following pinpoint test.
NOTE: Some PCM DTCs may inhibit A/C operation. If any PCM DTCs are retrieved, diagnose those first. Refer to PCM DTC Chart. PCM DTC Chart
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M1 CHECK THE BLOWER MOTOR OPERATION
- Ignition ON.
- Select PANEL mode.
- Observe blower motor operation and select each blower motor speed.
- Does the blower motor operate in all selections and change speed in each?
Yes
GO to M2.
No
If the blower motor does not operate in any setting, Go To Pinpoint Test R. Pinpoint Test R: the Blower Motor Is Inoperative
If the blower motor does not properly change speeds or shut OFF, Go To Pinpoint Test S. Pinpoint Test S: the Blower Motor Does Not Operate Correctly
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M2 CHECK AIRFLOW OPERATION
- Select the highest blower motor setting.
- NOTE: Refer to Description and Operation for proper airflow descriptions.
- While observing the airflow, select each of the airflow positions (PANEL, PANEL/FLOOR, FLOOR, FLOOR/DEFROST, DEFROST).
- Is the airflow directed to the proper outlets?
Yes
GO to M3.
No
Go To Pinpoint Test L. Pinpoint Test L: Incorrect/Erratic Direction of Airflow From Outlets
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M3 VERIFY TEMPERATURE CONTROL OPERATION
- Start the vehicle and allow it to reach normal operating temperature.
- With the A/C OFF, select PANEL mode.
- Change the temperature setting from the coldest to the warmest and back to the coldest.
- Does the temperature change between very warm to cool?
Yes
GO to M4.
No
If the temperature does not get very warm, Go To Pinpoint Test N. Pinpoint Test N: Insufficient, Erratic or No Heat
If the temperature does not change at all, Go To Pinpoint Test C. Pinpoint Test C: DTC B2266 or B2267
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M4 VERIFY THE A/C CLUTCH DOES NOT ENGAGE WITH A/C OFF
- With the A/C OFF, select PANEL mode.
- Select the coldest temperature setting.
- Is the outlet temperature close to ambient temperature?
Yes
GO to M5.
No
If the temperature is warmer than ambient temperature, INSPECT for binding or broken linkage. If no condition is found, INSTALL a new blend door actuator. TEST the system for normal operation.
If the outlet temperature is significantly colder than ambient temperature and the A/C compressor clutch cycles normally, Go To Pinpoint Test Q. Pinpoint Test Q: the Air Conditioning (A/C) Is Always on - A/C Mode Always Commanded on
If the outlet temperature is significantly colder than ambient temperature and the A/C compressor clutch does not cycle, Go To Pinpoint Test P. Pinpoint Test P: the Air Conditioning (A/C) Is Always on - A/C Compressor Does Not Cycle
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M5 VERIFY A/C CLUTCH ENGAGEMENT IN THE A/C MODE
- Make sure the ambient air temperature is above 2°C (35°F).
- Select PANEL mode.
- Press the A/C button (indicator ON).
- Does the A/C clutch engage when the PANEL and A/C button (indicator ON) is pressed?
Yes
GO to M6.
No
Go To Pinpoint Test O. Pinpoint Test O: the Air Conditioning (A/C) Is Inoperative
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M6 CHECK THE RECIRC OPERATION
- Press the RECIRC button (indicator OFF).
- Select PANEL mode.
- Select the highest blower motor setting.
- Observe airflow noise.
- Press the RECIRC button (indicator ON).
- Does the airflow noise increase when the RECIRC mode is selected (indicator ON)?
Yes
The system is operating normally.
No
Go To Pinpoint Test K. Pinpoint Test K: the Air Inlet Door Is Inoperative
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