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Inspection Procedure

REAR WINDOW DEFOGGER/HEATED OUTER MIRROR INSPECTION PROCEDURE

Step Inspection Action
1 VERIFY INSTRUMENT CLUSTER DTCs
  • Switch the ignition ON (engine off or on).
  • Perform the DTC inspection for the instrument cluster using the M-MDS. (See DTC INSPECTION [INSTRUMENT CLUSTER] .)
  • Is a DTC displayed?
Yes Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [INSTRUMENT CLUSTER] .)
No Go to the next step.
2 DETERMINE MALFUNCTIONING LOCATION BY PERFORMING PID/DATA MONITOR INSPECTION
Yes Go to Step 5.
No Go to the next step.
3 INSPECT REAR WINDOW DEFOGGER SWITCH CONDITION BY PERFORMING PID/DATA MONITOR INSPECTION
Yes Go to the next step.
No Replace the climate control unit, then go to Step 13.
(See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER] .)
(See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER] .)
4 INSPECT REAR WINDOW DEFOGGER OPERATION REQUEST SIGNAL FROM CLIMATE CONTROL UNIT BY PERFORMING PID/DATA MONITOR INSPECTION
Yes
NOTE:
  • The rear window defogger does not operate normally due to BCM control malfunction.
Replace the BCM, then go to Step 13.(See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION .)
No Replace the climate control unit, then go to Step 13.
(See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER] .)
(See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER] .)
5 INSPECT REAR WINDOW DEFOGGER RELAY
Yes Go to the next step.
No Replace the rear window defogger relay, then go to Step 13.
(See RELAY LOCATION .)
6 INSPECT REAR WINDOW DEFOGGER RELAY CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT
  • Verify that the rear window defogger relay is removed.
  • Connect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
  • Measure the voltage at rear window defogger relay terminals C and E (vehicle wiring harness side).
  • Is the voltage B+?
Yes Go to the next step.
No Inspect the DEFOG 30 A fuse.
  • If the fuse is blown:
    • Refer to the wiring diagram and verify if there is a common connector between DEFOG 30 A fuse and rear window defogger relay terminals C and E.

If there is a common connector:
  • Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to ground to determine the malfunctioning location.
    • Repair or replace the malfunctioning location.

If there is no common connector:
  • Repair or replace the wiring harness which is shorted to ground.
    • Replace the fuse.
    • If the fuse is damaged:
      • Replace the fuse.
  • If the fuse is normal:
    • Refer to the wiring diagram and verify if there is a common connector between positive battery terminal and rear window defogger relay terminals C and E.

If there is a common connector:
  • Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for an open circuit to determine the malfunctioning location.
    • Repair or replace the malfunctioning location.

If there is no common connector:
  • Repair or replace the wiring harness which has an open circuit.

    Go to Step 13.

7 INSPECT BCM CIRCUIT FOR SHORT TO GROUND
  • Verify that the rear window defogger relay is removed.
  • Disconnect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
  • Disconnect the BCM connector.
  • Inspect for continuity between the following terminals (wiring harness side):
    • BCM terminal 3K-body ground
  • Is there continuity?
Yes Go to the next step.
No Refer to the wiring diagram and verify if there is a common connector between BCM terminals 3K and rear window defogger relay terminal A.
If there is a common connector:
  • Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to ground to determine the malfunctioning location.
  • Repair or replace the malfunctioning location.

If there is no common connector:
  • Repair or replace the wiring harness which is shorted to ground.

After repair, go to next step.
8 INSPECT BCM CIRCUIT FOR SHORT TO POWER SUPPLY
Yes Go to the next step.
No Refer to the wiring diagram and verify if there is a common connector between BCM terminals 3K and rear window defogger relay terminal A.
If there is a common connector:
  • Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to power supply to determine the malfunctioning location.
  • Repair or replace the malfunctioning location.

If there is no common connector:
  • Repair or replace the wiring harness which is shorted to power supply.

After repair, go to next step.
9 INSPECT BCM CIRCUIT FOR OPEN CIRCUIT
  • Switch the ignition OFF (LOCK).
  • Disconnect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
  • Inspect for continuity between the following terminals (wiring harness-side):
    • BCM terminal 3K-rear window defogger relay terminal A
  • Is there continuity?
Yes Go to the next step.
No Refer to the wiring diagram and verify if there is a common connector between BCM terminals 3K and rear window defogger relay terminal A.
If there is a common connector:
  • Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for an open circuit to determine the malfunctioning location.
  • Repair or replace the malfunctioning location.

If there is no common connector:
  • Repair or replace the wiring harness which has an open circuit.

After repair, go to step 13.
10 INSPECT REAR WINDOW DEFOGGER AND HEATED OUTER MIRROR CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT
  • Install the rear window defogger relay. (See RELAY LOCATION .)
  • Reconnect all disconnected connectors.
  • Connect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
  • Switch the ignition ON (engine off or on).
  • Turn the rear window defogger switch on.
  • Measure the voltage at following terminals (wiring harness-side):
    • Rear window defogger terminal A
    • Heated outer mirror (LH) terminal A (with heated outer mirror)
      • Heated outer mirror (RH) terminal A (with heated outer mirror)
  • Is the voltage B+?
Yes Go to the next step.
No Inspect the M.DEF 7.5 A fuse.
  • If the fuse is blown:
    • Refer to the wiring diagram and verify if there is a common connector between M.DEF 7.5 A fuse and heated outer mirror (LH, RH) terminals A.

    If there is a common connector:

    • Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to ground to determine the malfunctioning location.
      • Repair or replace the malfunctioning location.

If there is no common connector:
  • Repair or replace the wiring harness which is shorted to ground.
    • Replace the fuse.
    • If the fuse is damaged:
      • Replace the fuse.
  • If the fuse is normal:
    • Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
  • rear window defogger relay terminal D and rear window defogger terminal A
  • rear window defogger relay terminal D and heated outer mirror (LH) terminal A (with heated outer mirror)
    • rear window defogger relay terminal D and heated outer mirror (RH) terminal A (with heated outer mirror)

If there is a common connector:
  • Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to ground or an open circuit to determine the malfunctioning location.
    • Repair or replace the malfunctioning location.

If there is no common connector:
  • Repair or replace the wiring harness which has an open circuit.

    Go to Step 13.

11 INSPECT REAR WINDOW DEFOGGER AND HEATED OUTER MIRROR FOR SHORT TO POWER SUPPLY
  • Turn the rear window defogger switch on.
  • Measure the voltage at following terminals (wiring harness-side):
    • Rear window defogger terminal A
    • Heated outer mirror (LH) terminal A (with heated outer mirror)
      • Heated outer mirror (RH) terminal A (with heated outer mirror)
  • Is the voltage 0 V?
Yes Go to the next step.
No Refer to the wiring diagram and verify if there is a common connector between the following terminals and rear window defogger relay terminal D.
  • Rear window defogger terminal A
  • Heated outer mirror (LH) terminal A (with heated outer mirror)
  • Heated outer mirror (RH) terminal A (with heated outer mirror)

If there is a common connector:
  • Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to power supply to determine the malfunctioning location.
  • Repair or replace the malfunctioning location.

If there is no common connector:
  • Repair or replace the wiring harness which is shorted to power supply.

After repair, go to step 13.
12 INSPECT REAR WINDOW DEFOGGER AND HEATED OUTER MIRROR
Yes Refer to the wiring diagram and verify if there is a common connector between the following terminals and body ground.
  • Rear window defogger terminal B (CONVERTIBLE TOP)
  • Rear window defogger terminal C (RETRACTABLE HARDTOP)
  • Heated outer mirror (LH) terminal G (with heated outer mirror)
  • Heated outer mirror (RH) terminal G (with heated outer mirror)

If there is a common connector:
  • Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for an open circuit or short to power supply to determine the malfunctioning location.
  • Repair or replace the malfunctioning location.

If there is no common connector:
  • Repair or replace the wiring harness which has an open circuit or short to power supply.

After repair, go to the next step.
No Repair the rear window defogger and heated outer mirror, then go to the next step.
(See REAR WINDOW DEFOGGER REPAIR .)
(See OUTER MIRROR GLASS REMOVAL .)
(See OUTER MIRROR GLASS INSTALLATION .)
13 VERIFY IF MALFUNCTION IS RESOLVED
  • Does the rear window defogger system operate normally?
Yes Explain the contents of the servicing to the customer.
No If the malfunction has not been resolved, repeat the inspection from Step 1.