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Home >> Mazda >> 2006 >> MX-5 Miata Base >> Repair and Diagnosis >> Body & Frame >> Door Locks >> Symptom Troubleshooting [Advanced Keyless System) >> No.3 Advanced Keyless Entry Function Inoperative >> Diagnostic Procedure
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Diagnostic Procedure

ADVANCED KEYLESS ENTRY FUNCTION INOPERATIVE DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1
  • Retrieve the advanced keyless system DTC using the WDS or equivalent.
  • Are there DTC displayed?
Yes Perform the applicable DTC diagnostic procedures.
No Go to the next step.
2
  • Did the customer attempt to operate each front doors and liftgate using the request switch?
Yes Go to the next step.
No Inspect the advanced keyless system operations using the request switch. If the advanced keyless system is inoperative, then go to the next step.
3
  • Prepare the followings:
    • Make sure that there is no transmitter (card key) inside the passenger compartment.
    • Close all doors including liftgate.
    • Remove the key from the steering lock.
    • Make sure that start knob is to the LOCK position. (Do not Press the knob)
    • Make sure that the transmitter (card key) is within the advanced keyless system operative area (within 80 cm {2.6 ft}  from front door)
  • Does the advanced keyless system operate properly?
Yes The system is normal. Explain the advanced keyless system operation.
No Go to the next step.
4
  • Replace with a transmitter (card key) battery known to be good.
  • Operate the transmitter (card key).
  • Does the keyless entry system operate properly?
Yes Replace the transmitter (card key). Then go to the next step.
No Go to the next step.
5
  • Measure the voltage at the keyless control module terminals 4H, 4J and 4L while operating the request switch.
    • Operate driver's side front door request switch (4H): 5.0 V  -->1.0 V or less
    • Operate passenger's side front door request switch (4J): 5.0 V  -->1.0 V or less
    • Operate liftgate request switch (4L): 5.0 V  -->1.0 V or less
  • Is the voltage as above?
Yes Go to the next step.
No Inspect and repair the applicable wiring harness as necessary, then go to the next step.
6
  • Measure the voltage at the following keyless control module terminal while operating the request switch.
    • Terminal 2A and 2B for exterior, RF keyless antenna
    • Terminal 2C and 2D for exterior, LF keyless antenna
    • Terminal 2E and 2F for exterior, rear keyless antenna
    • Terminal 2G and 2H for interior, trunk keyless antenna
    • Terminal 2I and 2J for interior, rear keyless antenna
    • Terminal 2K and 2L for interior, middle keyless antenna
    • Terminal 3G and 3H for interior, front keyless antenna
  • Is the voltage within 4.0-6.0 V  ?
Yes Go to the next step.
No Inspect and repair the applicable wiring harness between the keyless antenna and the keyless control module, then go to the next step.
7
  • Simulate the following keyless antenna using the WDS or equivalent:.
    • ANT_RF# (exterior, RF keyless antenna: terminals 2A and 2B)
    • ANT_LF# (exterior, LF keyless antenna: terminals 2C and 2D)
    • ANT_BK# (exterior, rear keyless antenna: terminals 2E and 2F)
    • ANT_INN1# (interior, trunk keyless antenna: terminals 2G and 2H)
    • ANT_INN2# (interior, rear keyless antenna: terminals 2I and 2J)
    • ANT_INN3# (interior, middle keyless antenna: terminals 2K and 2L)
    • ANT_INN4# (interior, front keyless antenna: terminals 3G and 3H)
  • Does each antenna operate properly (ON/OFF)?
Yes Go to the next step.
No Replace the faulted antenna, then go to the next step.
8
  • Measure the voltage at the keyless control module terminals 2U (keyless receiver) while operating the any request switch.
    • 5.0 V  -->1.0 V or less
  • Is the voltage as above?
Yes Go to the next step.
No
  • Inspect the wiring harness between the keyless receiver and the keyless control module.
    • If the harness is normal, replace the keyless receiver.
    • If the harness is malfunctioning, repair the wiring harness.
  • Go to the next step.
9
  • Measure the voltage at the keyless control module terminals 2R (BCM) while operating the request switch.
    • Unlock: 1.0 V or less-->B+  -->1.0 V or less
  • Is the voltage as above?
Yes Inspect and repair the wiring harness between the BCM and the keyless control module, then go to the next step.
No Inspect the keyless control module. If the keyless control module is malfunctioning, replace the module.
10
  • Does the keyless entry system operate properly?
Yes Troubleshooting completed. Explain repairs to the customers
No Re-inspect the malfunction symptoms, then repeat form Step 1 if malfunction recurs.