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.
Diagnostic Trouble Code (DTC) Chart
Diagnostics in this service information assume a certain skill level and knowledge of Ford-specific diagnostic practices. REFER to: Diagnostic Methods .
| Module | DTC | Description | Action |
|---|---|---|---|
| APIM | U2400:81 | Ethernet Failure With Gateway Module A (GWM): Invalid Serial Data Received | GO to Pinpoint Test A |
| APIM | U2400:92 | Ethernet Failure With Gateway Module A (GWM): Performance Or Incorrect Operation | GO to Pinpoint Test A |
| GWM | U2120:00 | Ethernet Learning Incomplete: No Sub Type Information | GO to Pinpoint Test C |
| GWM | U2401:00 | Ethernet Failure With Accessory Protocol Interface Module (APIM): No Sub Type Information | GO to Pinpoint Test B |
| GWM | U2401:81 | Ethernet Failure With Accessory Protocol Interface Module (APIM): Invalid Serial Data Received | GO to Pinpoint Test A |
| GWM | U2401:92 | Ethernet Failure With Accessory Protocol Interface Module (APIM): Performance Or Incorrect Operation | GO to Pinpoint Test A |
| GWM | U2402:00 | Ethernet Failure With Telematic Control Unit Module (TCU): No Sub Type Information | GO to Pinpoint Test B |
| GWM | U2402:81 | Ethernet Failure With Telematic Control Unit Module (TCU): Invalid Serial Data Received | GO to Pinpoint Test A |
| GWM | U2402:92 | Ethernet Failure With Telematic Control Unit Module (TCU): Performance Or Incorrect Operation | GO to Pinpoint Test A |
| GWM | U2403:81 | Ethernet Failure With Instrument Panel Cluster Control Module (IPC): Invalid Serial Data Received | GO to Pinpoint Test A |
| GWM | U2403:92 | Ethernet Failure With Instrument Panel Cluster Control Module (IPC): Performance Or Incorrect Operation | GO to Pinpoint Test A |
| GWM | U2404:81 | Ethernet Failure With Image Processing Module 'A' (IPMA): Invalid Serial Data Received | GO to Pinpoint Test A |
| GWM | U2404:92 | Ethernet Failure With Image Processing Module 'A' (IPMA): Performance Or Incorrect Operation | GO to Pinpoint Test A |
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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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