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Home >> Ford >> 2004 >> Mustang Mach 1, Standard >> Repair and Diagnosis >> Body & Frame >> Door Locks >> Keyless Entry System And Computer Operated Lock System >> Diagnosis And Testing >> Keyless Entry >> Inspection and Verification
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Inspection and Verification

  1. The keyless entry system is a generic electronic module (GEM).
  2. Verify the customer concern by using the remote transmitters to operate the keyless entry system.
  3. Visually inspect for the following obvious signs of mechanical and electrical damage.
    VISUAL INSPECTION CHART

    Mechanical Electrical
    • Binding latches
    • Central junction box (CJB) fuse(s):
      • (5A)
      • 19 (15A)
      • 25 (25A)
    • Battery junction box (BJB) fuse POWER WINDOWS (40A)
    • Damaged wiring harness
    • Loose or corroded connector(s)
    • Circuitry open/shorted
    • Damaged relays
    • Remote transmitter
    • Remote transmitter batteries
  4. If the concern remains after the inspection, connect the diagnostic tool to the data link connector (DLC) located beneath the instrument panel and select the vehicle to be tested from the diagnostic tool menu. If the diagnostic tool does not communicate with the vehicle:
    • check that the program card is correctly installed.
    • check the connections to the vehicle.
    • check the ignition switch position.
  5. If the diagnostic tool still does not communicate with the vehicle, refer to the diagnostic tool manual.
  6. Carry out the diagnostic tool data link test. If the diagnostic tool responds with:
    • SCP or ISO circuit fault; all electronic control units, no response/not equipped, refer to MODULE COMMUNICATIONS NETWORK .
    • No response/not equipped for GEM, GO to PINPOINT TEST A .
    • System passed, retrieve and record the continuous diagnostic trouble codes (DTCs), erase the continuous DTCs, and carry out the self-test diagnostics for the GEM.
  7. If the DTCs retrieved are related to the concern, go to the GENERIC ELECTRONIC MODULE (GEM) DIAGNOSTIC TROUBLE CODE (DTC) INDEX  to continue diagnostics.
  8. If no DTCs related to the concern are retrieved, proceed to Symptom Chart to continue diagnostics.