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.
Interior Lighting System DTCS
Diagnostics in this article assume a certain skill level and knowledge of Ford-specific diagnostic practices. REFER to: Diagnostic Methods .
| DTC | Description | Action |
|---|---|---|
| B1175:64 | Drivers Door Ajar Switch: Signal Plausibility Failure | If the courtesy lamps are inoperative from the driver door, GO to Pinpoint Test A If the courtesy lamps are always on, GO to Pinpoint Test C |
| B11E9:13 | Left Rear Door Ajar Switch: Circuit Open | GO to Pinpoint Test C |
| B11EA:13 | Right Rear Door Ajar Switch: Circuit Open | GO to Pinpoint Test C |
| B1306:13 | Liftgate Ajar Switch: Circuit Open | GO to Pinpoint Test C |
| B1318:13 | Right Front Door Ajar Switch: Circuit Open | GO to Pinpoint Test C |
| B131B:13 | Left Front Door Ajar Switch: Circuit Open | GO to Pinpoint Test C |
| B1D13:11 | Interior Lights Circuit "A": Circuit Short to Ground | If the interior courtesy lamps are always on, GO to Pinpoint Test C If the interior courtesy lamps are inoperative, GO to Pinpoint Test B |
| B1D13:12 | Interior Lights Circuit "A": Circuit Short To Battery | GO to Pinpoint Test B |
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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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