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Home >> Mazda >> 2012 >> 6 s Touring Plus >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Anti-Theft Systems >> Symptom Troubleshooting [Keyless Entry System] >> No.1 Keyless Entry System Does Not Operate Normally [Keyless Entry System] >> Diagnostic Procedure
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Diagnostic Procedure

STEP INSPECTION ACTION
1 INSPECT FOR MALFUNCTION IN BCM POWER SUPPLY CIRCUIT OR ELSEWHERE 
  • Did any of the following items operate during the keyless entry system operation inspection?
    • All doors lock/unlock
    • Hazard wiring light flashes
Yes Go to the next step.
No Inspect the connection of the BCM connectors, and go to Step 4.
2 INSPECT FOR MALFUNCTION IN KEYLESS SWITCH OR ELSEWHERE 
  • Did the following item operate during the keyless entry system operation inspection?
    • All doors lock/unlock
Yes Go to the next step.
No Go to Step 9.
3 INSPECT FOR MALFUNCTION IN DOOR LOCK ACTUATOR OR ELSEWHERE 
  • Did the following item operate during the keyless entry system operation inspection?
    • Hazard warning light flashes
Yes Go to the next step.
No Go to Step 11.
*4 INSPECT BCM POWER SUPPLY CIRCUIT 
  • Are the BCM power supply and voltage normal?
    • IG1 signal (terminal 3AB, 4A)
    • B+ signal (terminal 2D, 2J, 4B, 4C)
Yes Go to the next step.
No
  • Inspect for burnt fuse.
  • Inspect the power supply system wiring harness for an open or short circuit.
  • Then go to Step 14.
*5 INSPECT BCM GROUND CIRCUIT 
  • Is the BCM ground voltage normal?
    • 0V (terminal 1V, 2A)
Yes Go to the next step.
No Inspect the ground system wiring harness for open circuit.
Then go to Step 14.
*6 INSPECT DOOR SWITCH SIGNAL 
  • Monitor following BCM (door switch) PID using the M-MDS.
    • TR/LG_SW (Trunk lid latch switch)
    • DRSW_P (Passenger's door latch switch)
    • DRSW_D (Driver's door switch)
    • DRSW_LR (Rear door latch switch (LH))
    • DRSW_RR (Rear door latch switch (RH))
  • Are monitored PID values normal?
Yes Go to the next step.
No
*7 INSPECT DOOR SWITCH SIGNAL VOLTAGE 
  • Are the wiring harness between the BCM and each door latch switch normal?
    • Inspect each terminal (8B, 8D, 8F, 8H) under the following conditions.
  • Door closed: 1.0V or less 
  • Door open: B+ 
Yes Go to the next step.
No
  • Inspect the door switch.
  • Inspect the door switch system wiring harness for a short circuit.
  • Then go to Step 14.
8 INSPECT KEYLESS SWITCH 
  • Is the keyless switch normal?

    ON: 12V 

    OFF: 0V 

Yes Replace the BCM.
No Replace the keyless switch, then go to Step 14.
*9 INSPECT IF MALFUNCTION IS IN DOOR LOCK ACTUATOR, BCM GROUND CIRCUIT OR ELSEWHERE 
  • Measure the voltage at the BCM terminals 7I, 7M and 7K while operating the transmitter.
    • All doors locked: 1.0 V or less → B+ → 1.0 V or less  (7I terminal)
    • All doors unlocked: 1.0 V or less → B+ → 1.0 V or less  (7M terminal)
    • Driver-side door unlocked: 1.0 V or less → B+ → 1.0 V or less  (7K terminal)
  • Is the voltage as above?
Yes Go to the next step.
No
  • Inspect the wiring harness between BCM and the door lock actuator for an open or short circuit.
  • Inspect the door lock actuator.
  • Then go to Step 14.
10 INSPECT DOOR LOCK LINKAGE 
  • Operate the key cylinder and verify the door locks and unlock manually.
  • Does every door lock system work?
Yes Go to step 12.
No Inspect the door lock linkage then go to Step 14.
*11 INSPECT FOR MALFUNCTION IN THEFT-DETERRENT SYSTEM OR ELSEWHERE 
  • Is the theft-deterrent system equipped?
Yes Go to the next step.
No Go to step 13.
12 INSPECT BONNET SWITCH AND TRUNK SIGNAL 
  • Monitor following BCM PID using the M-MDS.
    • TR/LG_SW (trunk lid latch switch)
    • HOOD_SW (hood latch switch)
  • Are monitored PID values ON (open)?
Yes Normal operation (Hazard warning light flashing on vehicles with theft-deterrent system operates in conjunction with theft-deterrent system).
No Go to the next step.
*13 INSPECT TURN LIGHT SIGNAL CIRCUIT 
  • Measure voltage at the BCM terminals 8I, 8J, 1P (right side turn signal), 8K, 8L and 1R (left side turn signal) while operating hazard and/or turn signal on.
  • Are the terminal voltages are alternated between 1.0V or less and B+? 
Yes Verify the malfunction symptom again.
No
  • Inspect the wiring harnesses between the BCM and each turn light for a short circuit.
  • Inspect each turn light.
  • If these items are normal, replace the BCM.
*14 REINSPECT MALFUNCTION SYMPTOM AFTER REPAIR 
  • Does the keyless entry system operate properly?
Yes Troubleshooting completed.
Explain repairs to the customer.
No Reinspect the malfunction symptoms, then repeat from Step 1 if the malfunction recurs.