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 L4-1.6LFACTORY OEM SERVICE PROCEDURE
Control Module: Service and Repair
Transmission Control Module (TCM)
Removal
1. Using the scan tool, recover all module information before removing the Transmission Control Module (TCM). For additional information, refer to Transmission Adaptive Learning Transmission Adaptive Learning.
2. Remove the battery and battery tray.
3. Remove the Air Cleaner (ACL) assembly and the outlet pipe.
4. Using a suitable tool, detach the wiring harness from the battery tray bracket.
5. Remove the selector lever cable bracket bolt, the battery tray bracket nuts and the battery tray bracket.
6. Remove the wiring harness from the transaxle housing.
7. Detach the wiring harness clips from the Transmission Control Module (TCM) housing.
8. Disconnect the 2 TCM (Transmission Control Module) electrical connectors.
9. Remove the 4 TCM (Transmission Control Module) bolts.
10. Using a suitable flat blade screwdriver, carefully pry the TCM (Transmission Control Module) from the transaxle, at the location shown, and remove the TCM (Transmission Control Module), discard the O-rings.
Installation
1. Carefully inspect the TCM (Transmission Control Module) and the transaxle bore for debris or damage. Clean and/or repair as needed.
2. NOTE: Use a small amount of transmission fluid on the new O-rings prior to installation.
Install new O-rings if the TCM (Transmission Control Module) is being reused.
3. NOTICE: Do not force the TCM (Transmission Control Module) onto the transaxle or damage may occur.
NOTICE: Make sure the TCM (Transmission Control Module) sits flush on the transaxle or damage can occur.
Install the TCM (Transmission Control Module) on the transaxle. Apply light pressure to seat the O-rings. If the TCM (Transmission Control Module) does not push in place with light pressure, remove the TCM (Transmission Control Module) and slightly turn the TCM (Transmission Control Module) gears and retry installing the TCM (Transmission Control Module) on the transaxle.
4. Install the 4 TCM (Transmission Control Module) bolts.
- Tighten to 27 Nm (20 lb-ft).
5. Connect the 2 TCM (Transmission Control Module) electrical connectors.
6. Install the wiring harness clips on the TCM (Transmission Control Module) housing.
7. Install the wiring harness on the transaxle housing.
8. Install the battery tray bracket, battery tray bracket nuts and selector lever cable bracket bolt.
- Tighten to 10 Nm (89 lb-in).
9. Install the wiring harness onto the battery tray bracket.
10. Install the ACL (Air Cleaner) assembly and outlet pipe.
11. Install the battery tray and battery.
12. If a new TCM (Transmission Control Module) was installed, it will need to be reprogrammed to the latest calibration level available. For additional Information, refer to Transmission Adaptive Learning Transmission Adaptive Learning.
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.