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Home >> Mazda >> 2006 >> MX-5 Miata Base >> Repair and Diagnosis >> Body & Frame >> Door Locks >> Symptom Troubleshooting [Advanced Keyless System) >> No. 4 Advanced Keyless Start Function Inoperative >> Diagnostic Procedure
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Diagnostic Procedure

ADVANCED KEYLESS START 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
  • Attempt to start the engine using the key.
  • Does engine start?
Yes Go to the next step.
No Go to symptom troubleshooting flow No.3 in ENGINE -- SYMPTOM TROUBLESHOOTING .
3
  • Bring the transmitter (card key) inside the passenger compartment.
  • Measure the voltage at the keyless control module terminal 2N (push switch) while pushing the start knob.
  • Is the voltage 0 V  ?
Yes Go to the next step.
No
  • Inspect the wiring harness between the steering lock unit and keyless control.
    • If the harness is normal, replace the steering lock unit.
    • If the harness is malfunctioning, repair the wiring harness.
  • Go to the next step.
4
  • Replace with a transmitter (card key) battery known to be good.
  • Bring the transmitter (card key) inside the passenger compartment.
  • 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 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 Step 7.
No Inspect and repair the applicable wiring harness between the keyless antenna and the keyless control module, then go to the next step.
6
  • 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.
7
  • Measure the voltage at the keyless control module terminals 2U (keyless receiver) while pressing the start knob.
    • 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.
8
  • Does the keyless indicator light turn ON when pressing the start knob?
Yes Go to Step 10.
No Go to the next step.
9
  • Measure the voltage at the keyless control module terminals 2P while pressing the start knob.
    • 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 steering lock unit and the keyless control module.
    • If the harness is normal, replace the keyless control module.
    • If the harness is malfunctioning, repair the wiring harness.
  • Go to the next step.
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.