The vehicle has lost communication with the engine control module.
Have this diagnosed before driving further
Informational only. Consult a qualified mechanic.
Check fuses and grounds first. May need ECM diagnosis or replacement.
The U0100 OBD-II diagnostic trouble code (DTC) indicates: lost communication with ecm/pcm. This is a critical-severity network code that your vehicle's onboard diagnostics system triggers when the vehicle has lost communication with the engine control module. If your check engine light is on with this code, you should have the vehicle inspected immediately before driving further.
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