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Home >> Mazda >> 2012 >> 6 s Touring Plus >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Anti-Theft Systems >> On-Board Diagnostic [Advanced Keyless Entry System And Push Button Start System] >> DTC C0040:29 [Advanced Keyless Entry And Push Button Start System] >> Diagnostic Procedure
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Diagnostic Procedure

Step Inspection Action
1 INSPECT KEYLESS CONTROL MODULE CONNECTOR CONDITION 
  • Switch the ignition to off.
  • Disconnect the negative battery cable.
  • Disconnect the keyless control module connector.
  • Inspect the connector and terminals (corrosion, damage, pin disconnection).
  • Is there any malfunction?
 Yes Repair or replace the connector or terminals, then go to Step 7.
No Go to the next step.
2 INSPECT BRAKE SWITCH CIRCUIT FOR SHORT TO GROUND 
  • Inspect for continuity between the following terminals and body ground:
    • Brake switch terminal A (wiring harness-side)
    • Brake switch terminal B (wiring harness-side)
  • Is there continuity?
 Yes Repair or replace the wiring harness for a possible short to ground, then go to Step 5.
No Go to the next step.
3 INSPECT BRAKE SWITCH CIRCUIT FOR SHORT TO POWER SUPPLY 
  • Reconnect the negative battery cable.
  • Switch the ignition to ON.
  • Measure the voltage between brake switch terminal D (wiring harness-side) and body ground.
  • Is there any voltage?
 Yes Repair or replace the wiring harness for a possible short to power supply, then go to Step 5.
No Go to the next step.
4 INSPECT BRAKE SWITCH CIRCUIT FOR OPEN CIRCUIT 
  • Switch the ignition to off.
  • Disconnect the negative battery cable.
  • Inspect for continuity between the following terminals:
    • Brake switch terminal A (wiring harness-side) and keyless control module terminal 3E (wiring harness-side)
    • Brake switch terminal B (wiring harness-side) and battery positive terminal
    • Brake switch terminal C (wiring harness-side) and body ground
    • Brake switch terminal D (wiring harness-side) and keyless control module terminal 3S (wiring harness-side)
  • Is there continuity?
 Yes Go to the next step.
No Repair or replace the wiring harness for a possible open circuit, then go to the next step.
5 VERIFY TROUBLESHOOTING COMPLETED 
 Yes Go to the next step.
No Go to Step 8.
6 INSPECT BRAKE SWITCH CONNECTOR CONDITION 
  • Switch the ignition to off.
  • Disconnect the negative battery cable.
  • Disconnect the brake switch connector.
  • Inspect the connector and terminals (corrosion, damage, pin disconnection).
  • Is there any malfunction?
 Yes Repair or replace the connector or terminals.
Replace the brake switch, then go to the next step.
(See BRAKE PEDAL REMOVAL/INSTALLATION .)
No Replace the brake switch, then go to the next step.
(See BRAKE PEDAL REMOVAL/INSTALLATION .)
7 VERIFY TROUBLESHOOTING COMPLETED 
 Yes Repeat the inspection from Step 1.
If the malfunction recurs, replace the keyless control module, then go to the next step.
(See KEYLESS CONTROL MODULE REMOVAL/INSTALLATION [ADVANCED KEYLESS ENTRY AND PUSH BUTTON START SYSTEM] .)
No Go to the next step.
8 VERIFY THAT NO OTHER DTCs ARE PRESENT 
  • Are any DTCs present?
 Yes Go to the applicable DTC inspection.
(See DTC TABLE [ADVANCED KEYLESS ENTRY AND PUSH BUTTON START SYSTEM] .)
No DTC troubleshooting completed.


Step Inspection Action
1 INSPECT PCM CONNECTOR CONDITION 
  • Switch the ignition to off.
  • Disconnect the negative battery cable.
  • Disconnect the PCM connector.
  • Inspect the connector and terminals (corrosion, damage, pin disconnection).
  • Is there any malfunction?
 Yes Repair or replace the connector or terminals, then go to Step 9.
No Go to the next step.
2 INSPECT KEYLESS CONTROL MODULE CONNECTOR CONDITION 
  • Disconnect the keyless control module connector.
  • Inspect the connector and terminals (corrosion, damage, pin disconnection).
  • Is there any malfunction?
 Yes Repair or replace the connector or terminals, then go to Step 9.
No Go to the next step.
3 INSPECT BRAKE SWITCH CIRCUIT FOR SHORT TO GROUND 
  • Inspect for continuity between the following terminals and body ground:
    • Brake switch terminal C (wiring harness-side)
    • Brake switch terminal B (wiring harness-side)
  • Is there continuity?
 Yes Repair or replace the wiring harness for a possible short to ground, then go to Step 7.
No Go to the next step.
4 INSPECT BRAKE SWITCH CIRCUIT FOR SHORT TO POWER SUPPLY 
  • Reconnect the negative battery cable.
  • Switch the ignition to ON.
  • Measure the voltage between the following terminals and body ground:
    • PCM terminal 1BK (wiring harness-side)
    • PCM terminal 1BP (wiring harness-side)
    • Keyless control module terminal 3S (wiring harness-side)
  • Is there any voltage?
 Yes Repair or replace the wiring harness for a possible short to power supply, then go to Step 7.
No Go to the next step.
5 INSPECT BRAKE SWITCH CIRCUIT FOR OPEN CIRCUIT 
  • Switch the ignition to off.
  • Disconnect the negative battery cable.
  • Inspect for continuity between the following terminals:
    • Brake switch terminal C (wiring harness-side) and PCM terminal 1T (wiring harness-side)
    • Brake switch terminal B (wiring harness-side) and battery positive terminal
    • Brake switch terminal A (wiring harness-side) and PCM terminal 1BK (wiring harness-side)
    • Brake switch terminal A (wiring harness-side) and PCM terminal 1BP (wiring harness-side)
    • Brake switch terminal D (wiring harness-side) and keyless control module terminal 3S (wiring harness-side)
  • Is there continuity?
 Yes Go to the next step.
No Repair or replace the wiring harness for a possible open circuit, then go to Step 7.
6 INSPECT PCM 
  • Reconnect the PCM connector.
  • Reconnect the negative battery cable.
  • Switch the ignition to ON.
  • Measure the voltage between PCM terminal 1T (wiring harness-side) and body ground.
  • Is the voltage normal?

    (See PCM INSPECTION [MZI 3.7 V6] .)

 Yes Replace the PCM, then go to Step 9.
(See PCM REMOVAL/INSTALLATION [MZI 3.7 V6] .)
No Go to the next step.
7 VERIFY TROUBLESHOOTING COMPLETED 
 Yes Go to the next step.
No Go to Step 10.
8 INSPECT BRAKE SWITCH CONNECTOR CONDITION 
  • Switch the ignition to off.
  • Disconnect the negative battery cable.
  • Disconnect the brake switch connector.
  • Inspect the connector and terminals (corrosion, damage, pin disconnection).
  • Is there any malfunction?
 Yes Repair or replace the connector or terminals.
Replace the brake switch, then go to the next step.
(See BRAKE PEDAL REMOVAL/INSTALLATION .)
No Replace the brake switch, then go to the next step.
(See BRAKE PEDAL REMOVAL/INSTALLATION .)
9 VERIFY TROUBLESHOOTING COMPLETED 
 Yes Repeat the inspection from Step 1.
If the malfunction recurs, replace the keyless control module, then go to the next step.
(See KEYLESS CONTROL MODULE REMOVAL/INSTALLATION [ADVANCED KEYLESS ENTRY AND PUSH BUTTON START SYSTEM] .)
No Go to the next step.
10 VERIFY THAT NO OTHER DTCs ARE PRESENT 
  • Are any DTCs present?
 Yes Go to the applicable DTC inspection.
(See DTC TABLE [ADVANCED KEYLESS ENTRY AND PUSH BUTTON START SYSTEM] .)
No DTC troubleshooting completed.
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