ALL SWITCH/DIAL OPERATION DOES NOT RESPOND (REAR CLIMATE CONTROL UNIT) [FULL-AUTO AIR CONDITIONER]


id0703c1006800

DESCRIPTION
•  All switch operation of rear climate control unit does not respond
POSSIBLE CAUSE
•  Open circuit or short to ground in wiring harness between rear climate control unit terminal B and front body control module (FBCM) terminal 1C
•  Open circuit or short to power supply in wiring harness between rear climate control unit terminal R and body ground
•  Ground point floating, bad contact
•  Rear climate control unit malfunction


Diagnostic Procedure

•  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.

Step

Inspection

Action

1*
INSPECT REAR CLIMATE CONTROL UNIT IG2 SIGNAL
•  Switch the ignition ON (engine off or on).
•  Measure the voltage at the following terminals (wiring harness-side):
―  Rear climate control unit terminal B
•  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 rear climate control unit 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.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness.
Go to Step 3.
2*
INSPECT REAR CLIMATE CONTROL UNIT GND SIGNAL
•  Measure the voltage at the following terminals (wiring harness-side):
―  Rear climate control unit terminal R
•  Is the voltage 0 V?
Yes
Replace the rear climate control unit, then go to the next step.
No
Refer to the wiring diagram and verify if there is a common connector between the rear climate control unit terminal and ground point.
If there is a common connector:
•  Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness.
Go to the next step.
3
VERIFY THAT MALFUNCTION SYMPTOM DOES NOT RECUR AFTER REPAIR
•  Do the related parts operate according to the switch operation of the rear climate control unit?
Yes
Troubleshooting completed.
Explain repairs to customer.
No
Recheck malfunction symptoms, then repeat from Step 1 if the malfunction recurs.