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Home >> Mazda >> 2012 >> 5 Touring >> Repair and Diagnosis (Single Page) >> Body & Frame >> Door Locks >> Symptom Troubleshooting [Keyless Entry System] >> No.3 Keyless Entry Remote Transmitter Id Code Cannot Be Reprogrammed >> Diagnostic procedure
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Diagnostic procedure

STEP INSPECTION ACTION
1 INSPECT POWER SUPPLY FUSE 
  • Is the keyless receiver power supply fuse normal?
 Yes Go to the next step.
No Install an appropriate amperage fuse, then go to Step 6.
2 INSPECT IF MALFUNCTION IS IN WIRING HARNESS (NO CONTINUITY BETWEEN FUSE BLOCK AND KEYLESS RECEIVER) OR ELSEWHERE 
  • Measure the voltage at the following keyless receiver terminal:
    • Power supply signal (terminal A)
  • Is the voltage B+  ?
 Yes Go to the next step.
No Repair the wiring harness between the fuse block and keyless receiver, then go to Step 6.
3 INSPECT IF MALFUNCTION IS IN WIRING HARNESS (NO CONTINUITY BETWEEN KEYLESS RECEIVER AND GROUND) OR ELSEWHERE 
  • Is there continuity between keyless receiver terminal E and ground?
 Yes Go to the next step.
No Repair the wiring harness between the keyless receiver and ground, then go to Step 6.
4 INSPECT IF MALFUNCTION IS IN WIRING HARNESS (NO CONTINUITY BETWEEN KEYLESS RECEIVER AND BCM) OR ELSEWHERE 
  • Disconnect the keyless receiver connector and BCM connector.
  • Is there continuity between the following terminals?
    • 4K (BCM connector)-D (keyless receiver connector)
 Yes Go to the next step.
No Repair the wiring harness between the keyless receiver and BCM, then go to Step 6.
5
  • Measure the signal wave pattern for keyless receiver terminal D using an oscilloscope while the keyless entry remote transmitter is operated with the key not inserted into the ignition key cylinder.
  • Does the wave pattern change when the keyless entry remote transmitter is operated?
NOTE:
  • Perform the oscilloscope setting using 0.5 V/DIV (Y), 100 ms/DIV (X), DC range.
 Yes Replace the BCM, then go to the next step.
(See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION .)
No Replace the keyless receiver, then go to the next step.
(See KEYLESS RECEIVER REMOVAL/INSTALLATION .)
6 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.
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