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Home >> Ford >> 2004 >> Mustang Mach 1, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 278 (Keyless Entry System & Computer Operated Lock System) >> Diagnosis And Testing >> Keyless Entry >> Symptom Chart >> Symptom Chart
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Symptom Chart

WARNING: This page is about a different car, the 2003 Ford Mustang. However, it is still accessible from the selected car via links, so may be relevant.
SYMPTOM CHART

Condition Possible Sources Action
No communication with the generic electronic module (GEM)
  • Circuitry.
  • Central junction box (CJB) fuse 39 (5A).
  • GEM.
 Go To PINPOINT TEST A  .
All door locks are inoperative
  • Central junction box (CJB) fuse 19 (15A).
  • Battery junction box (BJB) fuse POWER WINDOWS (40A).
  • Circuitry.
  • Generic electronic module (GEM)
  • Switches.
  • Lock actuators.
 Go To PINPOINT TEST B  .
The doors do not lock/unlock using the remote transmitter
  • Remote transmitter.
  • Remote transmitter battery.
  • Remote transmitter programming.
  • Aftermarket system.
  • High power devices.
  • TV/radio transmission towers.
  • Generic electronic module (GEM).
 Go To PINPOINT TEST C  .
The luggage compartment door is inoperative using the remote transmitter
  • Central junction box (CJB) fuse 25 (25A).
  • Remote transmitter battery.
  • Remote transmitter.
  • Generic electronic module (GEM).
  • Circuitry.
  • Luggage compartment lid release relay.
 Go To PINPOINT TEST D  .
Panic feature is inoperative/does not operate correctly
  • Generic electronic module (GEM).
  • Driver door unlock relay.
  • Circuitry.
  • Remote transmitter and batteries.
  • Courtesy lamps.
  • Horn relay.
  • Horn.
  • Parklamps.
 Go To PINPOINT TEST E  .
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