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NO WARM AIRFLOW FROM VENT [FULL-AUTO AIR CONDITIONER]

NO WARM AIRFLOW FROM VENT [FULL-AUTO AIR CONDITIONER]


 id0703c1703400

Malfunction symptom

No warm airflow from vent

Description
•  No warm airflow even if airflow temperature setting is MAX HOT
Possible cause
•  Blower motor malfunction
•  Engine is overcooling
―  PCM detects DTCs
―  Thermostat malfunction
•  Malfunction due to engine coolant leakage
•  Heater core malfunction

Diagnostic Procedure

Step

Inspection

Action

1
VERIFY DTCs
•  Perform the DTC inspection for the following modules.
―  PCM
―  Dash-electrical supply unit
•  Is a DTC displayed?
Yes
Repair the malfunctioning location according to the applicable DTC troubleshooting.
No
Go to the next step.
2
VERIFY AIRFLOW CONDITION
•  Switch the ignition ON (engine off or on).
•  Turn the airflow volume control switch on.
•  Does air flow from the vents after operating the blower motor?
Yes
Go to the next step.
No
Go to the following malfunction symptom item.
3
VERIFY IF MALFUNCTION IS CAUSED BY ENGINE OVERCOOLING
•  Using the M-MDS, display the PCM PID [ECT].
•  Switch the ignition ON (engine off or on) and warm up the engine while idling.
•  Is the monitor value 80°C or more?
Yes
Go to the next step.
No
Go to the following malfunction symptom item.
4
VERIFY IF MALFUNCTION IS CAUSED BY LACK OF ENGINE COOLANT
•  Is the engine coolant amount normal?
Yes
Repair or replace the heater core and go to the repair completion verification.
No
Add engine coolant and verify that there is no leakage in the engine coolant passage.
•  If there is any malfunction
―  Repair or replace the malfunctioning location and perform the repair completion verification.
Repair completion verification
VERIFY THAT MALFUNCTION DOES NOT RECUR AFTER REPAIRS
•  Does warm air flow when the airflow temperature setting is MAX HOT?
Yes
Troubleshooting completed. (Explain repair contents to the customer)
No
Refer to the CAN (controller area network) malfunction diagnosis flow to inspect for a CAN communication error.
If the CAN communication is normal, perform the diagnosis from Step 1.