Pinpoint Test C: Unable To Duplicate The Customer Concern And No Diagnostic Trouble Codes (DTCS) Present
- Normal Operation and Fault Conditions
This pinpoint test tests the functions of the HVAC system and identifies the correct HVAC symptom pinpoint test.
Possible Sources
- Wiring, terminals or connectors
- PCM
- A/C clutch relay
- C1 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 C2 No If the blower motor does not operate in any setting, GO to Pinpoint Test J If the blower motor does not properly change speeds or shut off, GO to Pinpoint Test K - C2 CHECK AIRFLOW OPERATION
- Select the highest blower motor setting.
- While observing the airflow, select each of the airflow positions (PANEL, PANEL/FLOOR, FLOOR, FLOOR/DEFROST, DEFROST).
Is the airflow directed to the correct outlets?
Yes GO to C3 No GO to Pinpoint Test E - C3 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 C4 No If the temperature does not get very warm, GO to Pinpoint Test F If the temperature does not change at all, GO to Pinpoint Test I - C4 VERIFY THE A/C (AIR CONDITIONING) CLUTCH DOES NOT ENGAGE WITH A/C OFF
- With the engine running and the A/C off, select PANEL mode.
- Select the coldest temperature setting.
Is the outlet temperature close to ambient temperature?
Yes GO to C5 No If the temperature is warmer than ambient temperature, GO to Pinpoint Test I If the outlet temperature is significantly colder than ambient temperature and the A/C compressor clutch engages, GO to Pinpoint Test H - C5 VERIFY A/C (AIR CONDITIONING) CLUTCH ENGAGEMENT IN THE A/C (AIR CONDITIONING) MODE
- Make sure the ambient air temperature is above 4°C (39°F).
- With the engine running, select PANEL mode.
- Press the A/C button (indicator on).
Does the A/C clutch engage when in PANEL mode and the A/C button (indicator on) is pressed?
Yes GO to C6 No GO to Pinpoint Test G - C6 CHECK THE RECIRC OPERATION
- With the engine running, 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 D