NO.7 AMOUNT OF AIR BLOWING FROM REAR VENTS DOES NOT CHANGE

BME070301038209

7

Amount of air blowing from rear vents does not change.

DESCRIPTION

• Malfunction in rear blower system.

POSSIBLE CAUSE

• Malfunction in rear fan switch from rear climate control unit, rear main fan switch, or related wiring harnesses
• Malfunction in rear main fan switch, or related wiring harnesses
• Malfunction in rear blower resistor, rear blower relay, or related wiring harnesses
• Rear A/C unit malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY WHETHER MALFUNCTION IS IN REAR FAN SWITCH SYSTEM OR REAR MAIN FAN SWITCH SYSTEM
• Does air blow from rear vents when rear fan switch from rear climate control unit is on?
Yes
Go to Step 4.
No
Go to next step.
2
VERIFY THAT REAR MAIN FAN SWITCH IS REAR POSITIONED
• Is rear main fan switch in REAR position?
Yes
Go to next step.
No
Set rear main fan switch to REAR position, then go back to Step 1.
3
INSPECT REAR FAN SWITCH, REAR MAIN FAN SWITCH AND RELATED WIRING HARNESSES
• Inspect the following systems and electrical parts.
- Rear fan switch from rear climate control unit
- Rear main fan switch
- Related wiring harnesses
• Are they okay?
Yes
Go to next step.
No
Repair or replace malfunctioning part, then go to Step 8.
4
VERIFY WHETHER MALFUNCTION IS IN FAN FROM REAR A/C UNIT OR ELSEWHERE
• Does air blow from rear vents when rear main fan switch is on?
Yes
Go to Step 7.
No
Go to next step.
5
INSPECT REAR MAIN FAN SWITCH AND RELATED WIRING HARNESSES
• Inspect the following systems and electrical parts.
- Rear main fan switch
- Related wiring harnesses
• Are they okay?
Yes
Go to next step.
No
Repair or replace malfunctioning part, then go to Step 8.
6
INSPECT REAR BLOWER RESISTOR, REAR BLOWER RELAY AND RELATED WIRING HARNESSES
• Inspect the following systems and electrical parts.
- Rear blower resistor
- Rear blower relay
- Related wiring harnesses
• Are they okay?
Yes
Go to next step.
No
Repair or replace malfunctioning part, then go to Step 8.
7
INSPECT FAN FROM REAR A/C UNIT
• Inspect fan in rear A/C as follows.
- Is fan free of interference from rear A/C unit case?
- Is fan free of foreign material and obstructions?
• Is fan okay?
Yes
Check rear A/C unit intake vent for clogging, then go to next step.
No
Remove obstruction, repair or replace fan and rear A/C unit case, then go to next step.
8
VERIFY THAT MALFUNCTION SYMPTOM OCCURS AFTER REPAIR
• Does air blow out?
Yes
Troubleshooting completed. Explain repairs to customer.
No
Recheck malfunction symptoms, then repeat from Step 1 if malfunction recurs.