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.
2003 Ford Mustang Mach 1, AutomaticFACTORY OEM SERVICE PROCEDURE
Inspection and Verification: Notes
- The keyless entry system is a generic electronic module (GEM).
- Verify the customer concern by using the remote transmitters to operate the keyless entry system.
- Visually inspect for the following obvious signs of mechanical and electrical damage.
- If the concern remains after the inspection, connect the scan tool to the data link connector (DLC) located beneath the instrument panel and select the vehicle to be tested from the scan tool menu. If the scan 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.
- If the scan tool still does not communicate with the vehicle, refer to the scan tool manual.
- Carry out the DATA LINK DIAGNOSTIC TEST. If the scan tool responds with:
- CKT914, CKT915 or CKT70 = ALL ECUS NO RESP/NOT EQUIP, refer to MODULE COMMUNICATIONS NETWORK .
- NO RESP/NOT EQUIP 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.
- If the DTCs retrieved are related to the concern, go to the GEM DIAGNOSTIC TROUBLE CODE (DTC) INDEX to continue diagnostics.
- If no DTCs related to the concern are retrieved, proceed to Symptom Chart to continue diagnostics.
Factory Service Tools
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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.