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.
2012 Ford Fiesta S, Standard TransFACTORY OEM SERVICE PROCEDURE
Interior Lighting System DTCS
BODY CONTROL MODULE (BCM) DIAGNOSTIC TROUBLE CODE (DTC) LIST
| DTC | Description | Action |
|---|---|---|
| B1091:12 | Courtesy Lamp Sense: Circuit Short To Battery | GO to Pinpoint Test B . |
| B1175:92 | Drivers Door Ajar Switch: Performance Or Incorrect Operation | GO to Pinpoint Test D . |
| B1176:92 | Passenger Door Ajar Switch: Performance Or Incorrect Operation | GO to Pinpoint Test D . |
| B1178:92 | Boot/Trunk Ajar Switch: Performance Or Incorrect Operation | GO to Pinpoint Test C . |
| B11E9:92 | Left Rear Door Ajar Switch: Performance Or Incorrect Operation | GO to Pinpoint Test D . |
| B11EA:92 | Right Rear Door Ajar Switch: Performance Or Incorrect Operation | GO to Pinpoint Test D . |
| B12F1:11 | Ambient Lighting Zone 1 Output: Circuit Short To Ground | GO to Pinpoint Test H . |
| B12F1:15 | Ambient Lighting Zone 1 Output: Circuit Short To Battery Or Open | If the ambient lighting is inoperative, GO to Pinpoint Test H
. If the ambient lighting is always on, GO to Pinpoint Test J . |
| B1D14:11 | Interior Lights Circuit "B": Circuit Short To Ground | GO to Pinpoint Test B . |
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.