NO.5 WINDSHIELD FOGGED

id070300801900

5
Windshield fogged.
DESCRIPTION
•  Malfunction in A/C compressor control system and/or air intake mode switching system
•  A/C compressor does not operate while airflow mode is DEFROSTER or HEAT/DEF modes.
•  Air intake mode does not change to FRESH while airflow mode is in DEFROSTER or HEAT/DEF modes.
POSSIBLE CAUSE
•  Front climate control unit (B+ signal) system malfunction
•  Air intake actuator malfunction
•  Front climate control unit (RECIRCULATE, FRESH signal) system malfunction
•  A/C unit air intake door malfunction

•  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, inspect to make sure connectors, terminals and wiring harness are connected correctly and undamaged.

Diagnostic procedure

STEP

INSPECTION

ACTION
1
COOL AIR BLOW OUT INSPECTION
•  When both the A/C and fan switch in the front climate control unit are on, does cool air blow out from the front vent?
Yes
Go to the next step.
No
Go to Step 1 of troubleshooting index No.8.
2
INSPECT FRONT CLIMATE CONTROL UNIT POWER SUPPLY FUSE FOR B+ SIGNAL
•  Is the front climate control unit power supply fuse for B+ signal normal?
Yes
Go to the next step.
No
Inspect for a short to ground on blown fuse circuit.
•  Repair or replace if necessary. Install appropriate amperage fuse.
3
INSPECT AIR INTAKE ACTUATOR
•  Inspect the air intake actuator for followings.
―  Is there grease on the link?
―  Is the link securely and properly positioned?
―  Is the link free of obstructions?
•  Are the above items normal?
Yes
Go to the next step.
No
Apply grease or install the link properly and securely, remove obstruction, then go to Step 14.
*4
INSPECT WIRING HARNESS BETWEEN FUSE BLOCK AND FRONT CLIMATE CONTROL UNIT FOR CONTINUITY
•  Disconnect the front climate control unit connector (24-pin).
•  Turn the ignition switch to the ON position.
•  Measure the voltage at front climate control unit terminal 1B (B+ signal).
•  Is the voltage approx. 12 V?
Yes
Go to the next step.
No
Repair the wiring harness between the fuse block and front climate control unit, then go to Step 14.
*5
INSPECT WIRING HARNESS BETWEEN FRONT CLIMATE CONTROL UNIT AND GROUND FOR VOLTAGE
•  Measure the voltage at front climate control unit terminal 1X (Ground).
•  Is the voltage approx. 0V?
Yes
Go to the next step.
No
Repair the wiring harness between the front climate control unit and ground, then go to Step 14.
6
VERIFY WHETHER MALFUNCTION IS IN A/C UNIT AIR INTAKE DOOR OR ELSEWHERE
•  Turn the ignition switch to the LOCK position.
•  Connect the climate control unit connector (24-pin).
•  Remove the air intake actuator.
•  Turn the ignition switch to the ON position.
•  Set the fan switch to 4th position.
•  Does the air intake mode (RECIRCULATE, FRESH) change smoothly when the air intake link is operated by hand?
Yes
Go to the next step.
No
Go to Step 12.
7
INSPECT AIR INTAKE ACTUATOR
•  Inspect the air intake actuator.
•  Is it normal?
Yes
Go to the next step.
No
Replace the air intake actuator, go to Step 14.
8
INSPECT AIR INTAKE SELECTOR SWITCH AND DEFROSTER SWITCH IN FRONT CLIMATE CONTROL UNIT
•  Measure the voltage at front climate control unit connector (24-pin) terminals 1O and 1M.
•  Is it normal?
Yes
Go to the next step.
No
Replace the front climate control unit, then go to Step 14.
*9
INSPECT WIRING HARNESS BETWEEN FRONT CLIMATE CONTROL UNIT AND AIR INTAKE ACTUATOR FOR CONTINUITY
•  Turn the ignition switch to the LOCK position.
•  Is there continuity between the following front climate control unit terminals and air intake actuator terminals?
R.H.D.
―  Terminal A —Terminal 1M (RECIRCULATE signal)
―  Terminal C —Terminal 1O (FRESH signal)
L.H.D.
―  Terminal C —Terminal 1O (RECIRCULATE signal)
―  Terminal A —Terminal 1M (FRESH signal)
Yes
Go to the next step.
No
Repair the wiring harness between the front climate control unit and air intake actuator, then go to Step 14.
*10
INSPECT WIRING HARNESS BETWEEN FRONT CLIMATE CONTROL UNIT AND AIR INTAKE ACTUATOR FOR SHORT TO GROUND
•  Is there continuity between the following front climate control unit terminals and ground?
R.H.D.
―  Terminal 1M (RECIRCULATE signal)
―  Terminal 1O (FRESH signal)
L.H.D.
―  Terminal 1O (RECIRCULATE signal)
―  Terminal 1M (FRESH signal)
Yes
Repair the wiring harness between the front climate control unit and air intake actuator, then go to Step 14.
No
Go to the next step.
*11
INSPECT WIRING HARNESS BETWEEN FRONT CLIMATE CONTROL UNIT AND AIR INTAKE ACTUATOR FOR SHORT TO B+
•  Turn the ignition switch to the ON position
•  Measure the voltage at the following front climate control unit terminals.
R.H.D.
―  Terminal 1M (RECIRCULATE signal)
―  Terminal 1O (FRESH signal)
L.H.D.
―  Terminal 1O (RECIRCULATE signal)
―  Terminal 1M (FRESH signal)
•  Is the voltage approx. 12 V?
Yes
Repair the wiring harness between the front climate control unit and air intake actuator, then go to Step 14.
No
Replace the front climate control unit, then go to Step 14.
12
INSPECT A/C UNIT AIR INTAKE DOOR
•  Is there any foreign material or obstruction in the A/C unit air intake door?
Yes
Remove obstruction, then go to Step 14.
No
Go to the next step.
13
VERIFY THAT A/C UNIT AIR INTAKE DOOR IS POSITIONED SECURELY AND PROPERLY
•  Is the A/C unit air intake door securely and properly positioned?
Yes
Inspect the air intake door for cracks or damage, then go to the next step.
No
Install the air intake door securely in the proper position, then go to the next step.
14
VERFY REPAIR
•  Does the malfunction disappear?
Yes
Troubleshooting completed.
Explain repairs to customer.
No
Recheck malfunction symptoms, then repeat from Step 1 if the malfunction recurs.