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 ThunderbirdFACTORY OEM SERVICE PROCEDURE
Circuit Protection Devices
CIRCUIT PROTECTION DEVICES LOCATION
| Component | Location |
|---|---|
| Auxiliary Relay Box 1 | Behind seats, on vehicle crossbeam. See Figure. |
| Battery Junction Box | In luggage compartment, near battery. See Figure. |
| Central Junction Box | Behind right kick panel. |
| Fuel Pump Motor Diode | On right side of luggage compartment. |
| Interior Auxiliary Junction Box | Under left side of dash. |
| Mega Fuse | In luggage compartment, near battery junction box. See Figure. |
| PCM Power Diode | On right side of engine compartment. |
| Underhood Auxiliary Junction Box (AJB) | In right front of engine compartment. See Figure. |
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.