Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2004 Ford Mustang Mach 1, AutomaticFACTORY OEM SERVICE PROCEDURE
Keyless Entry System And Computer Operated Lock System
- Description And Operation
- Diagnosis And Testing
- Keyless Entry
- Notes
- Principles of Operation
- Inspection and Verification
- Generic Electronic Module (GEM) Diagnostic Trouble Code (DTC) Index
- Symptom Chart
- Pinpoint Tests
- Pinpoint Test A: No Communication With The Generic Electronic Module
- Pinpoint Test B: All Door Locks Are Inoperative
- Pinpoint Test C: The Doors Do Not Lock/Unlock Using The Remote Transmitter
- Pinpoint Test D: The Luggage Compartment Door Is Inoperative Using The Remote Transmitter
- Pinpoint Test E: Panic Feature Is Inoperative/Does Not Operate Correctly
- Pinpoint Test F: The Remote Keyless Entry Transmitter Is Out Of Synchronization
- Pinpoint Test G: The Remote Transmitter Has Poor Range Performance
- Keyless Entry
- General Procedures
- Removal And Installation
Factory Service Tools
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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