NO.8 AIRFLOW MODE FROM REAR VENTS DOES NOT CHANGE


BME070301038210

8

Airflow mode from rear vents does not change.

DESCRIPTION

• Malfunction in rear A/C unit's airflow system.

POSSIBLE CAUSE

• Malfunction in rear A/C unit's airflow mode lever or airflow mode crank
• Rear airflow mode and air mix actuator IG2 signal circuit malfunction
• Malfunction in rear airflow mode and air mix actuator, rear climate control unit's each signal circuit
• Malfunction in rear A/C unit's airflow mode door

• 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, check to make sure connectors, terminals and wiring harnesses are connected correctly and undamaged.

Diagnostic procedure

STEP

INSPECTION

ACTION

1
INSPECT REAR A/C UNIT'S REAR AIRFLOW MODE AND AIR MIX ACTUATOR
• Remove rear A/C unit's rear airflow mode and air mix actuator.
• Inspect rear A/C unit's airflow mode lever and crank.
- Is there grease on lever and crank?
- Are lever and crank securely in their proper positions?
• Are above items all okay?
Yes
Go to next step.
No
Apply grease or install lever and crank securely in their proper positions, then go to Step 9.
2
VERIFY WHETHER MALFUNCTION IS IN REAR AIRFLOW MODE AND AIR MIX ACTUATOR SYSTEM OR REAR A/C UNIT'S AIRFLOW MODE DOOR
• Turn ignition switch to ON position.
• Set rear main fan switch at third position.
• Is each rear airflow mode and air mix (VENT and COLD, 1/2 HOT, HEATand HOT) accessed smoothly when airflow mode crank is operated by hand?
Yes
Go to next step.
No
Go to next Step 7.
*3
INSPECT WIRING HARNESS BETWEEN FUSE BLOCK AND REAR AIRFLOW MODE AND AIR MIX ACTUATOR FOR CONTINUITY
• Test voltage at rear airflow mode and air mix actuator terminal F (motor drive).
• Is voltage approximately B+?
Yes
Go to next step.
No
Repair wiring harness between fuse block and rear airflow mode and air mix actuator, then go to Step 9.
4
INSPECT REAR AIRFLOW MODE AND AIR MIX ACTUATOR
• Inspect rear airflow mode and air mix actuator.
• Is it okay?
Yes
Go to next step.
No
Replace rear airflow mode and air mix actuator, then go to Step 9.
*5
INSPECT WIRING HARNESS BETWEEN REAR CLIMATE CONTROL UNIT AND REAR AIRFLOW MODE AND AIR MIX ACTUATOR FOR CONTINUITY
• Turn ignition switch to LOCK position.
• Disconnect rear climate control unit connector and rear airflow mode and air mix actuator connector.
• Inspect for continuity between the following terminals.
- Terminal F (GND signal)-Terminal G (rear airflow mode and air mix actuator)
- Terminal A (rear climate control unit)-Terminal A (rear airflow mode and air mix actuator)
- Terminal B (rear climate control unit)-Terminal B (rear airflow mode and air mix actuator)
- Terminal D (rear climate control unit)-Terminal C (rear airflow mode and air mix actuator)
- Terminal O (IG2 signal)-Terminal F (rear airflow mode and air mix actuator)
• Is there continuity?
Yes
Go to next step.
No
Repair wiring harness between rear climate control unit and rear airflow mode and air mix actuator, then go to Step 9.
*6
INSPECT WIRING HARNESS BETWEEN REAR CLIMATE CONTROL UNIT AND REAR AIRFLOW MODE AND AIR MIX ACTUATOR FOR SHORT TO GROUND
• Inspect for no continuity between the following terminals and ground.
- Terminal F (GND signal)-Terminal G (rear airflow mode and air mix actuator)
- Terminal A (rear climate control unit)-Terminal A (rear airflow mode and air mix actuator)
- Terminal B (rear climate control unit)-Terminal B (rear airflow mode and air mix actuator)
- Terminal D (rear climate control unit)-Terminal C (rear airflow mode and air mix actuator)
- Terminal O (IG2 signal)-Terminal F (rear airflow mode and air mix actuator)
• Is there no continuity?
Yes
Go to next step.
No
Repair wiring harness between rear climate control unit and rear airflow mode and air mix actuator, go to Step 9.
7
INSPECT REAR A/C UNIT
• Is there any foreign material or obstructions in rear A/C unit's airflow mode door?
Yes
Remove obstruction, then go to Step 9.
No
Go to next step.
8
INSPECT REAR A/C UNIT'S AIRFLOW MODE DOOR
• Inspect rear A/C unit's airflow mode door as follows.
- Is airflow mode door free of cracks and damage?
- Is airflow mode door securely and properly installed?
• Are above items okay?
Yes
Replace rear climate control unit, then go to next step.
No
Replace airflow mode door or install airflow mode door securely in proper position, then go to next step.
9
VERIFY THAT MALFUNCTION SYMPTOM OCCURS AFTER REPAIR
• Does airflow mode change?
Yes
Troubleshooting completed. Explain repairs to customer.
No
Recheck malfunction symptoms, then repeat from Step 1 if malfunction recurs.