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Home >> Mazda >> 2012 >> 6 s Touring Plus >> Repair and Diagnosis (Single Page) >> Body & Frame >> Door Locks >> On-Board Diagnostic [Advanced Keyless Entry System And Push Button Start System] >> DTC U0028:87 [Advanced Keyless Entry And Push Button Start System] >> Diagnostic Procedure
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Diagnostic Procedure

Step Inspection Action
1 INSPECT BCM CONNECTOR CONDITION 
  • Switch the ignition to off.
  • Disconnect the negative battery cable.
  • Disconnect the BCM 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 6.
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 6.
No Go to the next step.
3 INSPECT COMMUNICATION CIRCUIT FOR SHORT TO GROUND 
  • Inspect for continuity between BCM terminal 6J (wiring harness-side) and body ground.
  • Is there continuity?
 Yes Repair or replace the wiring harness for a possible short to ground, then go to Step 6.
No Go to the next step.
4 INSPECT COMMUNICATION CIRCUIT FOR OPEN CIRCUIT 
  • Inspect for continuity between BCM terminal 6J (wiring harness-side) and keyless control module terminal 2F (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 6.
5 INSPECT BCM 
  • Reconnect the disconnected connectors.
  • Reconnect the negative battery cable.
  • Switch the ignition to ON.
  • Measure the voltage between BCM terminal 6J (wiring harness-side) and body ground.
  • Is the voltage normal?

    (See BODY CONTROL MODULE (BCM) INSPECTION .)

 Yes Replace the BCM, then go to the next step.
(See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION .)
No Go to the next step.
6 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.
7 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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