AMOUNT OF AIR BLOWN FROM VENTS DOES NOT CHANGE [FULL-AUTO AIR CONDITIONER (E)]

Troubleshooting item	Amount of air blown from vents does not change
Description	• Blower motor does not operate even if airflow volume control switch is operated (no airflow from vent) • Blower motor operation does not change even if airflow volume control switch is operated (airflow volume from vent does not change)
Possible cause	• Dash-electrical supply unit detects DTC ― Detects DTC and activates fail-safe • Blower unit malfunction ― Blockage ― Interference between blower motor fan and case • Open circuit in blower motor power supply circuit • Short to ground in blower motor power supply circuit • Blower motor malfunction • Open circuit in blower motor signal circuit • Short to ground in blower motor signal circuit • Short to power supply in blower motor signal circuit • Climate control unit malfunction • Blower fan controller (built-in dash-electrical supply unit) malfunction

• When performing an asterisked (*) troubleshooting inspection, shake the wiring harness and connectors while performing the inspection to discover whether poor contact points are the cause of any intermittent malfunctions. If there is a problem, inspect make sure connectors, terminals and wiring harnesses are connected correctly and undamaged.

Step	Inspection	Action
1	PERFORM DASH-ELECTRICAL SUPPLY UNIT DTC INSPECTION • Perform the dash-electrical supply unit DTC inspection using the M-MDS. (See DTC INSPECTION.) • Are any DTCs displayed?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [DASH-ELECTRICAL SUPPLY UNIT (E)].)
No	Go to the next step.
2	INSPECT TO SEE WHETHER MALFUNCTION IS IN BLOWER UNIT OR ELSEWHERE • Switch the ignition ON (engine off or on). • Turn the airflow volume control switch on. • Recirculate air inside the vehicle. • Does the blower motor rotate?	Yes	Go to the next step.
No	Go to Step 4.
3	INSPECT BLOWER UNIT INTAKE VENT • Is blower unit intake vent restricted?	Yes	Remove obstruction, then perform the repair completion verification.
No	Inspect if there are any obstruction in the A/C unit passage, then perform the repair completion verification.
4*	INSPECT BLOWER MOTOR POWER SUPPLY CIRCUIT FOR SHORT TO GROUND AND OPEN CIRCUIT • Inspect the power supply circuit for an open circuit and short to ground. (See CIRCUIT INSPECTION.) • Is the circuit normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
5	INSPECT TO SEE WHETHER MALFUNCTION IS IN BLOWER MOTOR OR ELSEWHERE • Switch the ignition off. • Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION [(E)].) • Inspect the blower motor. (See BLOWER MOTOR INSPECTION.) • Is the blower motor normal?	Yes	Go to the next step.
No	Replace the blower motor, then perform the repair completion verification. (See BLOWER MOTOR REMOVAL/INSTALLATION [(E)].)
6	INSPECT BLOWER MOTOR CONTROL CIRCUIT FOR OPEN CIRCUIT • Inspect the applicable circuit for open circuit. (See CIRCUIT INSPECTION.) • Is the circuit normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
7	INSPECT BLOWER MOTOR CONTROL CIRCUIT FOR SHORT TO GROUND • Inspect the applicable circuit for a short to ground. (See CIRCUIT INSPECTION.) • Is the circuit normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
8	INSPECT BLOWER MOTOR CONTROL CIRCUIT FOR SHORT TO POWER SUPPLY • Inspect the applicable circuit for a short to power supply. (See CIRCUIT INSPECTION.) • Is the circuit normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
Repair completion verification	VERIFY THAT MALFUNCTION SYMPTOM DOES NOT RECUR AFTER REPAIR • Is air discharged from vent?	Yes	Troubleshooting completed. Explain repairs to customer.
No	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].) • If the CAN communication is normal, replace the climate control unit. (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER (E)].)

Step

Inspection

Action

PERFORM DASH-ELECTRICAL SUPPLY UNIT DTC INSPECTION

• Perform the dash-electrical supply unit DTC inspection using the M-MDS.

(See DTC INSPECTION.)

• Are any DTCs displayed?

Yes

Go to the applicable DTC inspection.

(See DTC TABLE [DASH-ELECTRICAL SUPPLY UNIT (E)].)

Go to the next step.

INSPECT TO SEE WHETHER MALFUNCTION IS IN BLOWER UNIT OR ELSEWHERE

• Switch the ignition ON (engine off or on).

• Turn the airflow volume control switch on.

• Recirculate air inside the vehicle.

• Does the blower motor rotate?

Yes

Go to the next step.

Go to Step 4.

INSPECT BLOWER UNIT INTAKE VENT

• Is blower unit intake vent restricted?

Yes

Remove obstruction, then perform the repair completion verification.

Inspect if there are any obstruction in the A/C unit passage, then perform the repair completion verification.

INSPECT BLOWER MOTOR POWER SUPPLY CIRCUIT FOR SHORT TO GROUND AND OPEN CIRCUIT

• Inspect the power supply circuit for an open circuit and short to ground.

(See CIRCUIT INSPECTION.)

• Is the circuit normal?

Yes

Go to the next step.

Repair or replace the malfunctioning location and perform the repair completion verification.

INSPECT TO SEE WHETHER MALFUNCTION IS IN BLOWER MOTOR OR ELSEWHERE

• Switch the ignition off.

• Disconnect the negative battery terminal.

(See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION [(E)].)

• Inspect the blower motor.

(See BLOWER MOTOR INSPECTION.)

• Is the blower motor normal?

Yes

Go to the next step.

Replace the blower motor, then perform the repair completion verification.

(See BLOWER MOTOR REMOVAL/INSTALLATION [(E)].)

INSPECT BLOWER MOTOR CONTROL CIRCUIT FOR OPEN CIRCUIT

• Inspect the applicable circuit for open circuit.

(See CIRCUIT INSPECTION.)

• Is the circuit normal?

Yes

Go to the next step.

Repair or replace the malfunctioning location and perform the repair completion verification.

INSPECT BLOWER MOTOR CONTROL CIRCUIT FOR SHORT TO GROUND

• Inspect the applicable circuit for a short to ground.

(See CIRCUIT INSPECTION.)

• Is the circuit normal?

Yes

Go to the next step.

Repair or replace the malfunctioning location and perform the repair completion verification.

INSPECT BLOWER MOTOR CONTROL CIRCUIT FOR SHORT TO POWER SUPPLY

• Inspect the applicable circuit for a short to power supply.

(See CIRCUIT INSPECTION.)

• Is the circuit normal?

Yes

Go to the next step.

Repair or replace the malfunctioning location and perform the repair completion verification.

Repair completion verification

VERIFY THAT MALFUNCTION SYMPTOM DOES NOT RECUR AFTER REPAIR

• Is air discharged from vent?

Yes

Troubleshooting completed.

Explain repairs to customer.

Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.

(See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].)

• If the CAN communication is normal, replace the climate control unit.

(See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER (E)].)

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