Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code (DTC) information

Condition
ECM-8400 is stored if one of the 5 volt supplies is short-circuited to supply voltage or ground or if there is an open-circuit in the circuit and the control module interprets it as a fault.

Substitute value
None.

Possible source

Signal too high:
- short-circuit to supply voltage in the signal cable
- open-circuit in the signal cable.

Signal too low:
- short-circuit to ground in the signal cable.

Fault symptom[s]
- poor performance
- uneven idle.