DTC 18


BHE070201038W07

DTC 18

Air mix actuator (potentiometer) system inspection

POSSIBLE CAUSE

• Air mix actuator malfunction
• Open circuit in wiring harness between A/C amplifier and air mix actuator
• Short circuit in wiring harness between A/C amplifier (terminal 2H) and air mix actuator (terminal E)

Diagnostic Procedure

STEP

INSPECTION

ACTION

1
• Inspect the air mix actuator. (See AIR MIX ACTUATOR INSPECTION.)
• Is it normal?
Yes
Go to the next step.
No
Replace the air mix actuator. (See AIR MIX ACTUATOR REMOVAL/INSTALLATION.)
2
• Disconnect the airflow mode actuator connector.
• Is the resistance between terminals 2H and 2P of the A/C amplifier connector (16-pin) 698 ohms or more?
Yes
Go to the next step.
No
Repair the wiring harness. (Short circuit)
3
• Disconnect the A/C amplifier connector (16-pin).
• Is the resistance between terminals 2O and 2P of the A/C amplifier connector (16-pin) 6.0 kilohms or less?
Yes
Go to the next step.
No
Repair the wiring harness. (Open circuit)
4
• Is the resistance between terminals 2H and 2O of the A/C amplifier connector (16-pin) 5.2 kilohms or less?
Yes
Inspect the connection at the A/C amplifier connector (16-pin). (See A/C AMPLIFIER INSPECTION [FULL-AUTO AIR CONDITIONER].)
No
Repair the wiring harness. (Open circuit)