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Home >> Mazda >> 2021 >> CX-9 Signature >> Repair and Diagnosis >> Body & Frame >> Windows >> Glass/Windows/Mirrors >> Rear Window Defogger/Heated Outer Mirror/Windshield Wiper De-ICER System Inspection >> Inspection Procedure

Inspection Procedure

REAR WINDOW DEFOGGER/HEATED OUTER MIRROR/WINDSHIELD WIPER DE-ICER SYSTEM INSPECTION DIAGNOSTIC 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 front climate control unit, then go to Step 16.
(See FRONT CLIMATE CONTROL UNIT REMOVAL/INSTALLATION .)
4 INSPECT REAR WINDOW DEFOGGER OPERATION REQUEST SIGNAL FROM FRONT CLIMATE CONTROL UNIT BY PERFORMING PID/DATA MONITOR INSPECTION Yes  
NOTE:
  • The rear window defogger does not operate normally due to FBCM control malfunction.

Replace the FBCM, then go to Step 16.
(See FRONT BODY CONTROL MODULE (FBCM) REMOVAL/INSTALLATION .)
No Replace the front climate control unit, then go to Step 16.
(See FRONT CLIMATE CONTROL UNIT REMOVAL/INSTALLATION .)
5 INSPECT REAR WINDOW DEFOGGER RELAY Yes Go to the next step.
No Replace the rear window defogger relay, then go to Step 16.
(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 terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
  • Measure the voltage at rear window defogger relay terminals D and A (vehicle wiring harness side).
  • Is the voltage B+?
Yes Go to the next step.
No Inspect the DEFOG 40 A fuse.
  • If the fuse is blown:
  • Refer to the wiring diagram and verify if there is a common connector between DEFOG 40 A fuse and rear window defogger relay terminals D and 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 if there is a common connector between positive battery terminal and rear window defogger relay terminals D and 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.

Go to Step 16.
7 INSPECT FBCM CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT Yes Go to the next step.
No Refer to the wiring diagram and verify if there is a common connector between FBCM terminal 1P and rear window defogger relay terminal 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 or 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 is shorted to ground or has an open circuit.

After repair, go to Step 16.
8 INSPECT FBCM CIRCUIT FOR SHORT TO POWER SUPPLY
  • Turn the rear window defogger switch on.
  • Measure the voltage at FBCM terminal 1P (vehicle wiring harness side).
  • Is the voltage B+?
Yes Refer to the wiring diagram and verify if there is a common connector between FBCM terminal 1P and rear window defogger relay terminal 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 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 16.
No Go to the next step.
9 INSPECT REAR WINDOW DEFOGGER CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT
  • Measure the voltage at following terminals (wiring harness-side):
  • Rear window defogger terminal 1A
  • Heated outer mirror (LH) terminal A (with heated outer mirror)
  • Heated outer mirror (RH) terminal A (with heated outer mirror)
  • Windshield wiper de-icer relay terminal A (with windshield wiper de-icer)
  • Is the voltage B+?
Yes With windshield wiper de-icer: Go to the next step.
Without windshield wiper de-icer: Go to step 14.
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:
  • rear window defogger relay terminal C and rear window defogger terminal 1A
  • rear window defogger relay terminal C and heated outer mirror (LH) terminal A (with heated outer mirror)
  • rear window defogger relay terminal C and heated outer mirror (RH) terminal A (with heated outer mirror)
  • rear window defogger relay terminal C and windshield wiper de-icer 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.

Go to Step 16.
10 INSPECT WINDSHIELD WIPER DE-ICER RELAY Yes Go to the next step.
No Replace the windshield wiper de-icer relay, then go to Step 16.
(See RELAY LOCATION .)
11 INSPECT WINDSHIELD WIPER DE-ICER RELAY CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT
  • Verify that the windshield wiper de-icer relay is removed.
  • Connect the negative battery terminal.

    (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)

  • Measure the voltage at windshield wiper de-icer relay terminal D (vehicle wiring harness side).
  • Is the voltage B+?
Yes Go to the next step.
No Inspect the WIPER, DEI 20 A fuse.
  • If the fuse is blown:
  • Refer to the wiring diagram and verify if there is a common connector between WIPER, DEI 20 A fuse and windshield wiper de-icer relay terminal D.

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 windshield wiper de-icer relay terminal D.

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 16.
12 INSPECT WINDSHIELD WIPER DE-ICER CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT Yes Go to the next step.
No Refer to the wiring diagram and verify if there is a common connector between windshield wiper de-icer relay terminal C and windshield wiper de-icer 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 or 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 is shorted to ground or has an open circuit.

After repair, go to Step 16.
13 INSPECT WINDSHIELD WIPER DE-ICER Yes Go to the next step.
No Repair the windshield, then go to Step 16. (See WINDSHIELD REMOVAL .)
(See WINDSHIELD INSTALLATION .)
14 INSPECT REAR WINDOW DEFOGGER Yes  
  • With heated outer mirror: Go to the next step.
  • Without heated outer mirror: Go to Step 16.
No Repair the rear window defogger, then go to Step 16.
(See REAR WINDOW DEFOGGER REPAIR .)
15 INSPECT HEATED OUTER MIRROR Yes Go to the next step.
No Repair the heated outer mirror, then go to the next step.
(See OUTER MIRROR GARNISH REMOVAL/INSTALLATION .)
(See OUTER MIRROR GLASS REMOVAL .)
(See OUTER MIRROR GLASS INSTALLATION .)
16 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.