AMOUNT OF AIR BLOWN FROM VENTS DOES NOT CHANGE [MANUAL AIR CONDITIONER]

id0703c2700400


7-Speed Type Airflow Volume Control Dial

DESCRIPTION
•  Malfunction in blower system
POSSIBLE CAUSE
•  HEATER 40 A fuse malfunction
•  Blower unit malfunction
•  Open or short circuit in wiring harness between climate control unit and blower relay
•  Blower relay malfunction
•  Blower motor malfunction
•  Blower fan controller malfunction
•  Climate control 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.

Diagnostic procedure

Step

Inspection

Action
1
INSPECT FUSE
•  Remove the HEATER 40 A fuse.
•  Is the fuse normal?
Yes
Go to the next step.
No
If the fuse is melted:
•  Repair or replace wiring harness for short to GND and replace the fuse.
If the fuse is deterioration:
•  Replace the fuse.
Then go to Step 15.
2
INSPECT TO SEE WHETHER MALFUNCTION IS IN BLOWER UNIT OR ELSEWHERE
•  Switch the ignition ON (engine off or on).
•  Turn the fan dial clockwise.
•  Recirculate air inside the vehicle.
•  Does the blower motor rotate smoothly?
Yes
Go to the next step.
No
Go to Step 4.
3
INSPECT BLOWER UNIT INTAKE VENT
•  Is blower unit intake vent clogged?
Yes
Remove obstruction, then go to Step 15.
No
Inspect if there are any obstruction in the A/C unit passage, then go to Step 15.
4*
INSPECT TO SEE WHETHER MALFUNCTION IS IN BLOWER RELAY SYSTEM OR BLOWER FAN CONTROLLER SYSTEM
•  Switch the ignition ON (engine off or on).
•  Turn the fan dial clockwise.
•  Measure the voltage at the following blower motor terminal.
―  Terminal A (blower motor operation signal)
•  Is voltage approx. 12 V?
Yes
Go to Step 8.
No
Go to the next step.
5*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (LACK OF CONTINUITY BETWEEN FUSE BLOCK AND BLOWER RELAY) OR ELSEWHERE
•  Measure the voltage at the following blower relay terminals.
―  Terminal A (B+ signal)
―  Terminal B (B+ signal)
•  Is the voltage approx. 12 V?
Yes
Go to the next step.
No
Refer to the wiring diagram and verify whether or not there is a common connector between blower relay terminal and HEATER 40 A fuse.
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.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness.
Go to Step 15.
6*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (LACK OF CONTINUITY BETWEEN BLOWER RELAY AND GROUND) OR ELSEWHERE
•  Measure the voltage at the following blower relay terminal.
―  Terminal D (GND signal)
•  Is the voltage approx. 0 V?
Yes
Go to the next step.
No
Refer to the wiring diagram and verify whether or not there is a common connector between 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.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness.
Go to Step 15.
7*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (LACK OF CONTINUITY BETWEEN BLOWER RELAY AND BLOWER FAN CONTROLLER) OR BLOWER RELAY
•  Measure the voltage at the following blower relay terminal.
―  Terminal C (blower motor operation signal)
•  Is the voltage approx. 12 V?
Yes
Repair the wiring harness for lack of continuity between the blower relay and blower fan controller, then go to Step 15.
No
Replace the blower relay, then go to Step 15.
8*
INSPECT BLOWER MOTOR
•  Inspect the blower motor.
•  Is the blower motor normal?
Yes
Go to the next step.
No
Replace the blower motor, then go to Step 15.
(See BLOWER MOTOR REMOVAL/INSTALLATION.)
9*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (LACK OF CONTINUITY BETWEEN BLOWER MOTOR AND BLOWER FAN CONTROLLER) OR ELSEWHERE
•  Measure the voltage at the following terminal of blower fan controller.
―  Terminal E (blower motor operation signal)
•  Is voltage approx. 12 V?
Yes
Go to the next step.
No
Refer to the wiring diagram and verify whether or not there is a common connector between blower motor terminal and blower fan controller 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.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness.
Go to Step 15.
10*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (LACK OF CONTINUITY BETWEEN BLOWER FAN CONTROLLER AND GROUND) OR ELSEWHERE
•   Measure the voltage at the following blower fan controller terminal.
―  Terminal C (GND)
•  Is the voltage approx. 0 V?
Yes
Go to the next step.
No
Refer to the wiring diagram and verify whether or not there is a common connector between blower fan controller terminal and ground.
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.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness.
Go to Step 15.
11
INSPECT BLOWER UNIT
•  Inspect the fan in blower unit.
―  Is the fan free of interference with the blower unit case?
―  Is the fan free of foreign material and obstruction?
•  Is the fan normal?
Yes
Go to the next step.
No
Remove obstruction, repair or replace the fan and A/C unit case, then go to Step 15.
12*
INSPECT BLOWER FAN CONTROLLER
•  Inspect the blower fan controller.
•  Is the blower fan controller normal?
Yes
Go to the next step.
No
Replace the blower fan controller, then go to Step 15.
(See BLOWER FAN CONTROLLER REMOVAL/INSTALLATION.)
13*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (LACK OF CONTINUITY BETWEEN BLOWER FAN CONTROLLER AND CLIMATE CONTROL UNIT) OR ELSEWHERE
•  Switch the ignition off.
•  Disconnect climate control unit connector.
•  Inspect for continuity at the following terminals between the blower fan controller and climate control unit.
―  Terminal B—I (blower motor speed control signal)
•  Is there continuity?
Yes
Go to the next step.
No
Refer to the wiring diagram and verify whether or not there is a common connector between blower fan controller terminal and climate control unit 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.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness.
Go to Step 15.
14*
INSPECT TO SEE WHETHER MALFUNCTION IS IN CLIMATE CONTROL UNIT OR WIRING HARNESS (SHORT TO GROUND IN WIRING HARNESS BETWEEN BLOWER FAN CONTROLLER AND CLIMATE CONTROL UNIT)
•  Inspect for continuity at the following terminal between the blower fan controller and ground.
―  Terminal B (blower motor speed control signal)—ground
•  Is there continuity?
Yes
Refer to the wiring diagram and verify whether or not there is a common connector between blower fan controller terminal and ground.
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.
Go to the next step.
No
Replace the climate control unit, then go to the next step.
(See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER].)
15
CONFIRM THAT MALFUNCTION SYMPTOM DOES NOT RECUR AFTER REPAIR
•  Is air discharged from vent?
Yes
Troubleshooting completed.
Explain repairs to customer.
No
Recheck malfunction symptoms, then repeat from Step 1 if the malfunction recurs.


4-Speed Type Airflow Volume Control Dial

DESCRIPTION
•  Malfunction in blower system
POSSIBLE CAUSE
•  HEATER 40 A fuse malfunction
•  Blower unit malfunction
•  Open or short circuit in wiring harness between fan switch and blower relay
•  Blower relay malfunction
•  Blower motor malfunction
•  Resistor malfunction
•  Fan switch 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.

Diagnostic procedure

Step

Inspection

Action
1
INSPECT FUSE
•  Remove the HEATER 40 A fuse.
•  Is the fuse normal?
Yes
Go to the next step.
No
If the fuse is melted:
•  Repair or replace wiring harness for short to GND and replace the fuse.
If the fuse is deterioration:
•  Replace the fuse.
Then go to Step 16.
2
INSPECT TO SEE WHETHER MALFUNCTION IS IN BLOWER UNIT OR ELSEWHERE
•  Switch the ignition ON (engine off or on).
•  Turn the fan dial clockwise.
•  Recirculate air inside the vehicle.
•  Does the blower motor rotate smoothly?
Yes
Go to the next step.
No
Go to Step 4.
3
INSPECT BLOWER UNIT INTAKE VENT
•  Is blower unit intake vent clogged?
Yes
Remove obstruction, then go to Step 16.
No
Inspect if there are any obstruction in the A/C unit passage, then go to Step 16.
4*
INSPECT TO SEE WHETHER MALFUNCTION IS IN BLOWER RELAY SYSTEM OR RESISTOR SYSTEM
•  Switch the ignition ON (engine off or on).
•  Turn the fan dial clockwise.
•  Measure the voltage at the following blower motor terminal.
―  Terminal A (blower motor operation signal)
•  Is voltage approx. 12 V?
Yes
Go to Step 10.
No
Go to the next step.
5*
INSPECT TO SEE WHETHER MALFUNCTION IS IN BLOWER MOTOR
•  Switch the ignition ON (engine off or on).
•  Turn the fan dial clockwise.
•  Measure the voltage at the following blower motor terminal.
―  Terminal B (blower motor operation signal)
•  Is voltage approx. 12 V?
Yes
Go to the next step.
No
Go to Step 7.
6*
INSPECT BLOWER MOTOR
•  Inspect the blower motor.
•  Is the blower motor normal?
Yes
Go to Step 16.
No
Replace the blower motor, then go to Step 16.
(See BLOWER MOTOR REMOVAL/INSTALLATION.)
7*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (LACK OF CONTINUITY BETWEEN FUSE BLOCK AND BLOWER RELAY) OR ELSEWHERE
•  Measure the voltage at the following blower relay terminals.
―  Terminal A (B+ signal)
―  Terminal B (B+ signal)
•  Is the voltage approx. 12 V?
Yes
Go to the next step.
No
Refer to the wiring diagram and verify whether or not there is a common connector between blower relay terminal and HEATER 40 A fuse.
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.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness.
Go to Step 16.
8*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (LACK OF CONTINUITY BETWEEN BLOWER RELAY AND GROUND) OR ELSEWHERE
•  Measure the voltage at the following blower relay terminal.
―  Terminal D (GND signal)
•  Is the voltage approx. 0 V?
Yes
Go to the next step.
No
Refer to the wiring diagram and verify whether or not there is a common connector between 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.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness.
Go to Step 16.
9*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (LACK OF CONTINUITY BETWEEN BLOWER RELAY AND RESISTOR) OR BLOWER RELAY
•  Measure the voltage at the following blower relay terminal.
―  Terminal C (blower motor operation signal)
•  Is the voltage approx. 12 V?
Yes
Repair the wiring harness for lack of continuity between the blower relay and resistor, then go to Step 16.
No
Replace the blower relay, then go to Step 16.
10*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (LACK OF CONTINUITY BETWEEN BLOWER MOTOR AND RESISTOR) OR ELSEWHERE
•  Measure the voltage at the following terminal of resistor.
―  Terminal A (blower motor operation signal)
•  Is voltage approx. 12 V?
Yes
Go to the next step.
No
Refer to the wiring diagram and verify whether or not there is a common connector between blower motor terminal and resistor 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.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness.
Go to Step 16.
11*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (LACK OF CONTINUITY BETWEEN FAN SWITCH AND GROUND) OR ELSEWHERE
•  Disconnect the negative battery cable.
•   Inspect for continuity at the following terminals between the fan switch and ground.
―  Terminal A (blower motor operation signal)—ground
•  Is there continuity?
Yes
Go to the next step.
No
Refer to the wiring diagram and verify whether or not there is a common connector between resistor terminal and ground.
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.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness.
Go to Step 16.
12
INSPECT BLOWER UNIT
•  Inspect the fan in blower unit.
―  Is the fan free of interference with the blower unit case?
―  Is the fan free of foreign material and obstruction?
•  Is the fan normal?
Yes
Go to the next step.
No
Remove obstruction, repair or replace the fan and blower unit case, then go to Step 16.
13*
INSPECT RESISTOR
•  Inspect the resistor.
•  Is the resistor normal?
Yes
Go to the next step.
No
Replace the resistor, then go to Step 16.
(See RESISTOR REMOVAL/INSTALLATION.)
14*
INSPECT FAN SWITCH
•  Inspect the fan switch.
•  Is the fan switch normal?
Yes
Go to the next step.
No
Replace the fan switch, then go to Step 16.
(See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER].)
15*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (LACK OF CONTINUITY BETWEEN RESISTOR AND FAN SWITCH) OR ELSEWHERE
•  Switch the ignition off.
•  Disconnect fan switch connector.
•  Inspect for continuity at the following terminals between the resistor and fan switch.
―  Terminal D—F (blower motor speed control signal)
―  Terminal B—E (blower motor speed control signal)
―  Terminal C—C (blower motor speed control signal)
―  Terminal A—D (blower motor speed control signal)
•  Is there continuity?
Yes
Go to the next step.
No
Refer to the wiring diagram and verify whether or not there is a common connector between resistor terminal and fan switch 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.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness.
Go to the next step.
16
CONFIRM THAT MALFUNCTION SYMPTOM DOES NOT RECUR AFTER REPAIR
•  Is air discharged from vent?
Yes
Troubleshooting completed.
Explain repairs to customer.
No
Recheck malfunction symptoms, then repeat from Step 1 if the malfunction recurs.