AMOUNT OF AIR BLOWN FROM FRONT VENTS DOES NOT CHANGE [FULL-AUTO AIR CONDITIONER]

DESCRIPTION

• Front blower motor does not operate even if airflow volume control switch is operated (no airflow from vent)

• Front blower motor operation does not change even if airflow volume control switch is operated (airflow volume from vent does not change)

POSSIBLE CAUSE

• HEATER 40 A fuse malfunction

• Front blower relay malfunction

• Front blower unit malfunction

― Clogging

― Interference between blower motor fan and case

• Front blower motor malfunction

• Front body control module (FBCM) malfunction

• Front climate control unit malfunction

• Open circuit or short to power supply in wiring harness between body ground and front blower motor terminal A

• Open circuit or short to ground or short to power supply in wiring harness between the following terminals:

― Front blower motor terminal B and front climate control unit terminal 1T

• Open circuit or short to ground in wiring harness between the following terminals:

― Front blower relay terminal A — HEATER 40 A fuse

― Front blower relay terminal B — HEATER 40 A fuse

― Front blower relay terminal C — front blower motor terminal C

• Open circuit or short to power supply in wiring harness between the following terminals:

― Front blower relay terminal D — Front body control module (FBCM) terminal 2Z

• 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	VERIFY FRONT BLOWER MOTOR OPERATION • Switch the ignition ON (engine off or on). • Set the airflow volume control dial to 1 or more. • Set the air intake mode to REC. • Does the front blower motor in the front A/C unit rotate smoothly?	Yes	Go to the next step.
1		No	Go to Step 3.
2	INSPECT BLOWER UNIT FOR CLOGGING • Is there clogging in the vent of the blower unit?	Yes	Remove the obstruction, then go to Step 11.
2		No	Verify that there is no obstruction in the air duct between the blower unit and the front A/C unit, there is no air filter clogging, and the evaporator is not frosted (frozen), then go to Step 11.
3^*	INSPECT VOLTAGE AT FRONT BLOWER MOTOR TERMINAL • Switch the ignition ON (engine off or on). • Set the airflow volume control dial to 6 or more. • Measure the voltage at the following terminals (wiring harness-side): ― Front blower motor terminal C • Is the voltage B+?	Yes	Go to Step 9.
3^*		No	Go to the next step.
4	INSPECT FUSE • Inspect HEATER 40 A fuse • Is the fuse normal?	Yes	Go to the next step.
4		No	If the fuse is blown: • Refer to the wiring diagram and verify whether or not there is a common connector between HEATER 40 A fuse and front blower motor / front blower relay terminal. If there is a common connector: ― Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground. ― Repair or replace the malfunctioning part. If there is no common connector: ― Repair or replace the wiring harness which has a short to ground. • Replace the fuse. If the fuse is damaged: • Replace the fuse. Then go to Step 11.
5^*	INSPECT VOLTAGE AT FRONT BLOWER RELAY TERMINAL • Measure the voltage at the following terminals: ― Front blower relay terminal A ― Front blower relay terminal B • Is the voltage B+?	Yes	Go to the next step.
5^*		No	Refer to the wiring diagram and verify whether or not there is a common connector between HEATER 40 A fuse terminal and front blower relay terminal. If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness which has a open circuit. Go to Step 11.
6^*	INSPECT VOLTAGE AT FRONT BLOWER RELAY TERMINAL • Measure the voltage at the following terminals: ― Front blower relay terminal D • Is the voltage approx. 0 V?	Yes	Go to Step 8.
6^*		No	Go to the next step.
7^*	INSPECT VOLTAGE AT FRONT BODY CONTROL MODULE (FBCM) TERMINAL • Measure the voltage at the following terminal. ― Front body control module (FBCM) terminal 2Z • Is the voltage approx. 0 V?	Yes	Refer to the wiring diagram and verify whether or not there is a common connector between front blower relay terminal and front body control module (FBCM) terminal. If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness. Go to Step 11.
7^*		No	Replace the front body control module (FBCM). (See FRONT BODY CONTROL MODULE (FBCM) REMOVAL/INSTALLATION.) Go to Step 11.
8^*	INSPECT VOLTAGE AT FRONT BLOWER RELAY TERMINAL • Measure the voltage at the following terminals: ― Front blower relay terminal C • Is the voltage B+?	Yes	Refer to the wiring diagram and verify whether or not there is a common connector between front blower motor terminal and front blower relay terminal. If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness. Go to Step 11.
8^*		No	Replace the front blower relay, then go to Step 11. (See RELAY LOCATION.)
9	INSPECT FRONT BLOWER MOTOR • Inspect the the front blower motor. (See FRONT BLOWER MOTOR INSPECTION.) • Is the front blower motor normal?	Yes	Go to the next step.
9		No	Replace the front blower motor, then go to Step 11. (See FRONT BLOWER MOTOR REMOVAL/INSTALLATION.)
10	VERIFY THAT THERE IS NO OBSTRUCTION IN FRONT BLOWER MOTOR FAN ROTATION • Inspect the front blower motor fan in the blower unit. ― Is the fan free of interference with the blower unit case? ― Is the fan free of foreign matter and obstructions? • Is the fan normal?	Yes	Replace the front climate control unit, go to the next step. (See FRONT CLIMATE CONTROL UNIT REMOVAL/INSTALLATION.)
10		No	Remove the obstruction or repair/replace the front blower motor fan, blower unit case, then go to the next step. (See BLOWER UNIT REMOVAL/INSTALLATION.) (See BLOWER UNIT DISASSEMBLY/ASSEMBLY.)
11	VERIFY THAT MALFUNCTION SYMPTOM DOES NOT RECUR AFTER REPAIR • Is air discharged from vent?	Yes	Troubleshooting completed. Explain repairs to customer.
11		No	Recheck malfunction symptoms, then repeat from Step 1 if the malfunction recurs.