DUAL A/C CONTROL DOES NOT OPERATE [FULL-AUTO AIR CONDITIONER]


id0703c1701100

DESCRIPTION
•  Driver or passenger side temperature control dial does not operate individually
•  Temperature control operates normally except for dual A/C control function
POSSIBLE CAUSE
•  Air mix door malfunction (driver or passenger-side)
•  Air mix actuator malfunction (driver or passenger-side)
•  Open or short circuit in wiring or poor connection between climate control unit and air mix actuator (driver or passenger-side)
•  Climate control unit malfunction

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

Diagnostic Procedure

Step

Inspection

Action

1
VERIFY SYMPTOM
•  Turn on the A/C.
•  Perform the dual A/C control function for driver and passenger side individually.
•  Is it either the temperature control on driver side or passenger side?
Yes
Go to the next step.
No
Go to Step 12.
2
INSPECT TO SEE WHETHER MALFUNCTION IS IN AIR MIX DOOR OR ELSEWHERE
•  Turn on the A/C.
•  Change temperature control on the suspected side while in dual mode.
•  Does the air mix door on the suspect side move smoothly?
Yes
Go to Step 8.
No
Go to the next step.
3
INSPECT AIR MIX ACTUATOR
•  Inspect the air mix actuator on the suspect side.
•  Is the air mix actuator normal?
Yes
Go to the next step.
No
Replace the air mix actuator on the suspected side, then go to Step 15.
4*
INSPECT AIR MIX ACTUATOR CIRCUIT FOR SHORT TO GROUND
•  Disconnect the climate control unit connector.
•  Inspect for continuity between the following terminals (wiring harness-side) and body ground:
Driver-side (L.H.D.):
―  Climate control unit terminal 1J
―  Climate control unit terminal 1L
Passenger-side (L.H.D.):
―  Climate control unit terminal 2C
―  Climate control unit terminal 2A
Driver-side (R.H.D.):
―  Climate control unit terminal 2C
―  Climate control unit terminal 2A
Passenger-side (R.H.D.):
―  Climate control unit terminal 1J
―  Climate control unit terminal 1L
•  Is there continuity?
Yes
Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and air mix actuator 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.
Go to Step 15.
No
Go to the next step.
5*
INSPECT AIR MIX ACTUATOR CIRCUIT FOR OPEN CIRCUIT
•  Air mix actuator and climate control unit connectors are disconnected.
•  Inspect for continuity between the following terminals (wiring harness-side):
Driver-side (L.H.D.):
―  Climate control unit terminal 1J—air mix actuator terminal B
―  Climate control unit terminal 1L—air mix actuator terminal C
Passenger-side (L.H.D.):
―  Climate control unit terminal 2C—air mix actuator terminal B
―  Climate control unit terminal 2A—air mix actuator terminal C
Driver-side (R.H.D.):
―  Climate control unit terminal 2C—air mix actuator terminal B
―  Climate control unit terminal 2A—air mix actuator terminal C
Passenger-side (R.H.D.):
―  Climate control unit terminal 1J—air mix actuator terminal B
―  Climate control unit terminal 1L—air mix actuator terminal C
•  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 climate control unit terminal and air mix actuator 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 an open circuit.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has an open circuit.
Go to Step 15.
6*
INSPECT AIR MIX ACTUATOR CIRCUIT FOR SHORT TO POWER SUPPLY
•  Air mix actuator and climate control unit connectors are disconnected.
•  Connect the negative battery terminal.
•  Switch the ignition ON (engine off or on).
•  Measure the voltage at the following terminals (wiring harness-side):
Driver-side (L.H.D.):
―  Climate control unit terminal 1J
―  Climate control unit terminal 1L
Passenger-side (L.H.D.):
―  Climate control unit terminal 2C
―  Climate control unit terminal 2A
Driver-side (R.H.D.):
―  Climate control unit terminal 2C
―  Climate control unit terminal 2A
Passenger-side (R.H.D.):
―  Climate control unit terminal 1J
―  Climate control unit terminal 1L
•  Is the voltage 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 climate control unit terminal and air mix actuator 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 power supply.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has a short to power supply.
Go to Step 15.
7
INSPECT AIR MIX DOOR
•  Inspect the suspect side air mix door.
•  Is the air mix door normal?
Yes
Replace the climate control unit, then go to Step 15.
No
Remove the obstruction or replace A/C unit case on the suspected side, then go to Step 15.
8*
INSPECT AIR MIX ACTUATOR POSITION SENSOR
•  Inspect the air mix actuator position sensor on the suspected side.
•  Is the air mix actuator position sensor normal?
Yes
Go to the next step.
No
Replace the air mix actuator on the suspected side, then go to Step 15.
9*
INSPECT AIR MIX ACTUATOR (POSITION SENSOR) CIRCUIT FOR SHORT TO GROUND
•  Disconnect the climate control unit connector.
•  Inspect for continuity between the following terminals (wiring harness-side) and body ground:
Driver-side (L.H.D.):
―  Climate control unit terminal 2K
Passenger-side (L.H.D.):
―  Climate control unit terminal 2I
Driver-side (R.H.D.):
―  Climate control unit terminal 2I
Passenger-side (R.H.D.):
―  Climate control unit terminal 2K
•  Is there continuity?
Yes
Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and air mix actuator 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.
Go to Step 15.
No
Go to the next step.
10*
INSPECT AIR MIX ACTUATOR (POSITION SENSOR) CIRCUIT FOR OPEN CIRCUIT
•  Air mix actuator and climate control unit connectors are disconnected.
•  Inspect for continuity between the following terminals (wiring harness-side):
Driver-side (L.H.D.):
―  Climate control unit terminal 2K—air mix actuator terminal F
―  Climate control unit terminal 1C—air mix actuator terminal G
―  Climate control unit terminal 1Q—air mix actuator terminal E
Passenger-side (L.H.D.):
―  Climate control unit terminal 2I—air mix actuator terminal F
―  Climate control unit terminal 1C—air mix actuator terminal E
―  Climate control unit terminal 1Q—air mix actuator terminal G
Driver-side (R.H.D.):
―  Climate control unit terminal 2I—air mix actuator terminal F
―  Climate control unit terminal 1C—air mix actuator terminal E
―  Climate control unit terminal 1Q—air mix actuator terminal G
Passenger-side (R.H.D.):
―  Climate control unit terminal 2K—air mix actuator terminal F
―  Climate control unit terminal 1C—air mix actuator terminal G
―  Climate control unit terminal 1Q—air mix actuator terminal E
•  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 climate control unit terminal and air mix actuator 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 an open circuit.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has an open circuit.
Go to Step 15.
11*
INSPECT AIR MIX ACTUATOR (POSITION SENSOR) CIRCUIT FOR SHORT TO POWER SUPPLY
•  Air mix actuator and climate control unit connectors are disconnected.
•  Connect the negative battery terminal.
•  Switch the ignition ON (engine off or on).
•  Measure the voltage at the following terminals (wiring harness-side):
Driver-side (L.H.D.):
―  Climate control unit terminal 2K
Passenger-side (L.H.D.):
―  Climate control unit terminal 2I
Driver-side (R.H.D.):
―  Climate control unit terminal 2I
Passenger-side (R.H.D.):
―  Climate control unit terminal 2K
•  Is the voltage 0 V?
Yes
Replace the climate control unit, then go to Step 15.
No
Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and air mix actuator 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 power supply.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has a short to power supply.
Go to Step 15.
12*
INSPECT AIR MIX ACTUATOR (POSITION SENSOR) CIRCUIT FOR SHORT TO GROUND
•  Switch the ignition off.
•  Disconnect the negative battery terminal.
•  Disconnect the climate control unit connector.
•  Disconnect the air mix actuator connector.
•  Inspect for continuity between the following terminals (wiring harness-side) and body ground:
―  Climate control unit terminal 1C
―  Climate control unit terminal 1Q
•  Is there continuity?
Yes
Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and each actuator / sensor 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.
Go to Step 15.
No
Go to the next step.
13*
INSPECT AIR MIX ACTUATOR (POSITION SENSOR) CIRCUIT FOR OPEN CIRCUIT
•  Air mix actuator and climate control unit connectors are disconnected.
•  Inspect for continuity between the following terminals (wiring harness-side):
Driver-side (L.H.D.):
―  Climate control unit terminal 1C—air mix actuator terminal G
―  Climate control unit terminal 1Q—air mix actuator terminal E
Passenger-side (L.H.D.):
―  Climate control unit terminal 1C—air mix actuator terminal E
―  Climate control unit terminal 1Q—air mix actuator terminal G
Driver-side (R.H.D.):
―  Climate control unit terminal 1C—air mix actuator terminal E
―  Climate control unit terminal 1Q—air mix actuator terminal G
Passenger-side (R.H.D.):
―  Climate control unit terminal 1C—air mix actuator terminal G
―  Climate control unit terminal 1Q—air mix actuator terminal E
•  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 climate control unit terminal and air mix actuator 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 an open circuit.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has an open circuit.
Go to Step 15.
14*
INSPECT AIR MIX ACTUATOR (POSITION SENSOR) CIRCUIT FOR SHORT TO POWER SUPPLY
•  Air mix actuator and climate control unit connectors are disconnected.
•  Connect the negative battery terminal.
•  Switch the ignition ON (engine off or on).
•  Measure the voltage at the terminals (wiring harness-side):
―  Climate control unit terminal 1C
―  Climate control unit terminal 1Q
•  Is the voltage 0 V?
Yes
Replace the climate control unit.
Go to the next Step.
No
Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and each actuator / sensor 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 power supply.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has a short to power supply.
Go to the next step.
15
VERIFY THAT MALFUNCTION SYMPTOMS DO NOT RECUR AFTER REPAIR
•  Can the temperatures for the driver-side and passenger-side be adjusted independently?
Yes
Troubleshooting completed. Explain repairs to customer.
No
Recheck malfunction symptoms, then repeat from Step 1 if malfunction recurs.