AMOUNT OF AIR BLOWN FROM FRONT VENTS DOES NOT CHANGE [CLIMATE CONTROL SYSTEM]

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Note
•  There are two types of front climate control unit, type A and type B.
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Front Climate Control Unit Type A

DESCRIPTION
•  Malfunction in front blower system
POSSIBLE CAUSE
•  HEATER 40 A fuse malfunction
•  Front blower unit malfunction
•  Open or short circuit in wiring harness between front climate control unit and front blower relay
•  Front blower relay malfunction
•  Front blower motor malfunction
•  Front 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
•  Switch the ignition off.
•  Disconnect the negative battery terminal.
•  Remove the HEATER 40 A fuse.
•  Is the fuse normal?
Yes
Go to the next step.
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 15.
2
INSPECT TO SEE WHETHER MALFUNCTION IS IN FRONT BLOWER UNIT OR ELSEWHERE
•  Connect the negative battery terminal.
•  Switch the ignition ON (engine off or on).
•  Turn the airflow volume control switch on.
•  Recirculate air inside the vehicle.
•  Does the front blower motor rotate?
Yes
Go to the next step.
No
Go to Step 4.
3
INSPECT FRONT BLOWER UNIT INTAKE VENT
•  Is front blower unit intake vent restricted?
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 FRONT BLOWER RELAY SYSTEM OR ELSEWHERE
•  Turn the airflow volume control switch on.
•  Measure the voltage at the following terminal (wiring harness side).
?  Front blower motor terminal C (front blower motor operation signal)
•  Is voltage B+?
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 FRONT BLOWER RELAY) OR ELSEWHERE
•  Measure the voltage at the following terminals (wiring harness side).
?  Front blower relay terminal A (B+ signal)
?  Front blower relay terminal B (B+ signal)
•  Is the voltage B+?
Yes
Go to the next step.
No
Refer to the wiring diagram and verify whether or not there is a common connector between front 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 FRONT BLOWER RELAY AND GROUND) OR ELSEWHERE
•  Measure the voltage at the following terminal (wiring harness side).
?  Front blower relay terminal D (ground)
•  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 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.
•  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 FRONT BLOWER RELAY AND FRONT BLOWER MOTOR) OR FRONT BLOWER RELAY
•  Measure the voltage at the following terminal (wiring harness side).
?  Front blower relay terminal C (front blower motor operation signal)
•  Is the voltage B+?
Yes
Repair the wiring harness for lack of continuity between the front blower relay and front blower motor, then go to Step 15.
No
Replace the front blower relay, then go to Step 15.
(See RELAY LOCATION.)
8
INSPECT TO SEE WHETHER MALFUNCTION IS IN FRONT BLOWER MOTOR OR ELSEWHERE
•  Switch the ignition off.
•  Disconnect the negative battery terminal.
•  Inspect the front blower motor.
•  Is the front blower motor normal?
Yes
Go to the next step.
No
Replace the front blower motor, then go to Step 15.
(See FRONT BLOWER MOTOR REMOVAL/INSTALLATION.)
9*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (LACK OF CONTINUITY BETWEEN FRONT BLOWER MOTOR AND FRONT CLIMATE CONTROL UNIT) OR ELSEWHERE
•  Front blower motor connector is disconnected.
•  Disconnect the front climate control unit connector.
•  Inspect for continuity between the following terminals (wiring harness-side).
?  Front blower motor terminal B—front climate control unit terminal 1H
•  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 front blower motor terminal and front 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.
10*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (SHORT TO GROUND BETWEEN FRONT BLOWER MOTOR AND FRONT CLIMATE CONTROL UNIT) OR ELSEWHERE
•  Inspect for continuity between the following terminal (wiring harness-side) and body ground.
?  Front blower motor terminal B
•  Is there continuity?
Yes
Refer to the wiring diagram and verify whether or not there is a common connector between front blower motor terminal and front 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.
No
Go to the next step.
11*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (SHORT TO POWER SUPPLY BETWEEN FRONT BLOWER MOTOR AND FRONT CLIMATE CONTROL UNIT) OR ELSEWHERE
•  Connect the negative battery terminal.
•  Switch the ignition on (engine off or on).
•  Measure the voltage at the following terminal (wiring harness side).
?  Front blower motor terminal B
•  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 front blower motor terminal and front 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.
12*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (SHORT TO POWER SUPPLY BETWEEN FRONT BLOWER MOTOR AND BODY GROUND) OR ELSEWHERE
•  Measure the voltage at the following terminal (wiring harness side).
?  Front blower motor terminal A
•  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 front blower motor terminal and body 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.
13*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (LACK OF CONTINUITY BETWEEN FRONT BLOWER MOTOR AND BODY GROUND) OR ELSEWHERE
•  Switch the ignition off.
•  Disconnect the negative battery terminal.
•  Inspect for continuity between the following terminal (wiring harness-side) and body ground.
?  Front blower motor terminal A
•  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 front blower motor terminal and body 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.
14
INSPECT FRONT BLOWER UNIT
•  Inspect the fan in front blower unit.
?  Is the fan free of interference with the front blower unit case?
?  Is the fan free of foreign matter and obstructions?
•  Is the fan normal?
Yes
Replace the front climate control unit, then go to the next step.
(See FRONT CLIMATE CONTROL UNIT REMOVAL/INSTALLATION.)
No
Remove obstruction, repair or replace the fan and front blower unit case, then go to the next step.
15
VERIFY 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.


Front Climate Control Unit Type B

DESCRIPTION
•  Malfunction in front blower system
POSSIBLE CAUSE
•  HEATER 40 A fuse malfunction
•  Front blower unit malfunction
•  Open or short circuit in wiring harness between front climate control unit and front blower relay
•  Front blower relay malfunction
•  Front blower motor malfunction
•  Front 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
•  Switch the ignition off.
•  Disconnect the negative battery terminal.
•  Remove the HEATER 40 A fuse.
•  Is the fuse normal?
Yes
Go to the next step.
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 15.
2
INSPECT TO SEE WHETHER MALFUNCTION IS IN FRONT BLOWER UNIT OR ELSEWHERE
•  Connect the negative battery terminal.
•  Switch the ignition ON (engine off or on).
•  Turn the airflow volume control switch on.
•  Recirculate air inside the vehicle.
•  Does the front blower motor rotate?
Yes
Go to the next step.
No
Go to Step 4.
3
INSPECT FRONT BLOWER UNIT INTAKE VENT
•  Is front blower unit intake vent restricted?
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 FRONT BLOWER RELAY SYSTEM OR ELSEWHERE
•  Turn the airflow volume control switch on.
•  Measure the voltage at the following terminal (wiring harness side).
?  Front blower motor terminal C (front blower motor operation signal)
•  Is voltage B+?
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 FRONT BLOWER RELAY) OR ELSEWHERE
•  Measure the voltage at the following terminals (wiring harness side).
?  Front blower relay terminal A (B+ signal)
?  Front blower relay terminal B (B+ signal)
•  Is the voltage B+?
Yes
Go to the next step.
No
Refer to the wiring diagram and verify whether or not there is a common connector between front 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 FRONT BLOWER RELAY AND GROUND) OR ELSEWHERE
•  Measure the voltage at the following terminal (wiring harness side).
?  Front blower relay terminal D (ground)
•  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 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.
•  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 FRONT BLOWER RELAY AND FRONT BLOWER MOTOR) OR FRONT BLOWER RELAY
•  Measure the voltage at the following terminal (wiring harness side).
?  Front blower relay terminal C (front blower motor operation signal)
•  Is the voltage B+?
Yes
Repair the wiring harness for lack of continuity between the front blower relay and front blower motor, then go to Step 15.
No
Replace the front blower relay, then go to Step 15.
(See RELAY LOCATION.)
8
INSPECT TO SEE WHETHER MALFUNCTION IS IN FRONT BLOWER MOTOR OR ELSEWHERE
•  Switch the ignition off.
•  Disconnect the negative battery terminal.
•  Inspect the front blower motor.
•  Is the front blower motor normal?
Yes
Go to the next step.
No
Replace the front blower motor, then go to Step 15.
(See FRONT BLOWER MOTOR REMOVAL/INSTALLATION.)
9*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (LACK OF CONTINUITY BETWEEN FRONT BLOWER MOTOR AND FRONT CLIMATE CONTROL UNIT) OR ELSEWHERE
•  Front blower motor connector is disconnected.
•  Disconnect the front climate control unit connector.
•  Inspect for continuity between the following terminals (wiring harness-side).
?  Front blower motor terminal B—front climate control unit terminal 1T
•  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 front blower motor terminal and front 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.
10*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (SHORT TO GROUND BETWEEN FRONT BLOWER MOTOR AND FRONT CLIMATE CONTROL UNIT) OR ELSEWHERE
•  Inspect for continuity between the following terminal (wiring harness-side) and body ground.
?  Front blower motor terminal B
•  Is there continuity?
Yes
Refer to the wiring diagram and verify whether or not there is a common connector between front blower motor terminal and front 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.
No
Go to the next step.
11*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (SHORT TO POWER SUPPLY BETWEEN FRONT BLOWER MOTOR AND FRONT CLIMATE CONTROL UNIT) OR ELSEWHERE
•  Connect the negative battery terminal.
•  Switch the ignition on (engine off or on).
•  Measure the voltage at the following terminal (wiring harness side).
?  Front blower motor terminal B
•  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 front blower motor terminal and front 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.
12*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (SHORT TO POWER SUPPLY BETWEEN FRONT BLOWER MOTOR AND BODY GROUND) OR ELSEWHERE
•  Measure the voltage at the following terminal (wiring harness side).
?  Front blower motor terminal A
•  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 front blower motor terminal and body 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.
13*
INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (LACK OF CONTINUITY BETWEEN FRONT BLOWER MOTOR AND BODY GROUND) OR ELSEWHERE
•  Switch the ignition off.
•  Disconnect the negative battery terminal.
•  Inspect for continuity between the following terminal (wiring harness-side) and body ground.
?  Front blower motor terminal A
•  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 front blower motor terminal and body 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.
14
INSPECT FRONT BLOWER UNIT
•  Inspect the fan in front blower unit.
?  Is the fan free of interference with the front blower unit case?
?  Is the fan free of foreign matter and obstructions?
•  Is the fan normal?
Yes
Replace the front climate control unit, then go to the next step.
(See FRONT CLIMATE CONTROL UNIT REMOVAL/INSTALLATION.)
No
Remove obstruction, repair or replace the fan and front blower unit case, then go to the next step.
15
VERIFY 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.