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P1678

DTC P1678: FPTDR Signal Line Failure - A/T Model

1. Reset the PCM.
2. Start the engine and wait 60 seconds.

Is DTC P1678 indicated?

YES - Go to step 3.

NO - Intermittent failure, system is OK at this time. Check for poor connections or loose wires at the ABS/TCS control unit and at the PCM.

3. Turn the ignition switch OFF.
4. Disconnect the ABS/TCS control unit 16P connector.
5. Start the engine and wait 10 seconds.

Is DTC P1678 indicated?

YES - Substitute a known-good ABS/TCS control unit and recheck. If the symptom/indication goes away, replace the original ABS/TCS control unit.

NO - Substitute a known-good PCM and recheck. If the symptom/indication goes away, replace the original PCM.