Troubleshooting Troubleshooting procedure Step 1
Inspection Inspect coolant temperature
Yes
Go to next step.
No
Warm up engine to normal operation temperature, then go to step 21.
Verify whether malfunction is in air mix actuator (+5v signal) system or elsewhere.
Yes
Go to step 6.
l
Turn ignition switch to on position.
No
Go to next step.
l
Measure the voltage at terminal c (+5v signal) of air mix actuator.
l
Is voltage approximately equivalent to +5v? Yes
Inspect air mix actuator, then go to step 21.
No
Go to next step.
Yes
Go to next step.
No
Repair wiring harness between rear climate control unit and air mix actuator, go to step 21.
Verify whether malfunction is in wiring harness (short circuit to ground between rear climate control unit and air mix actuator) or in rear climate control unit.
Yes
Repair wiring harness between rear climate control unit and air mix actuator, go to step 21.
l
No
Replace rear climate control unit, go to step 21.
Yes
Go to next step.
No
Repair wiring harness between rear climate control unit and air mix actuator, go to step 21.
Yes
Repair wiring harness between rear
l
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*3
*4
*5
*6
*7
Action
Is coolant warmed up sufficiently?
Inspect air mix actuator for continuity. l
Disconnect air mix actuator connector
l
Measure the voltage at terminal c (+5v signal) of air mix actuator
l
Is voltage approximately equivalent to 5v?
Inspect continuity of wiring harness between rear climate control unit and air mix actuator. l
Turn ignition switch to lock position.
l
Disconnect rear climate control connector.
l
Is there continuity between terminal c (+5v signal) of air mix actuator conduct and terminal h of rear climate control unit?
Is there continuity between terminal c (+5v signal) of air mix actuator and ground?
Inspect continuity of wiring harness between rear climate control unit and air mix actuator. l
Turn ignition switch to lock position.
l
Disconnect connectors of rear climate control unit from air mix actuator.
l
Is there continuity between terminal f of rear climate control unit and terminal e of air mix actuator?
Inspect wiring harness between rear climate U-28
