Diagnostic Trouble Code (DTC) Information ECM-983A
Condition
Diagnostic trouble code (DTC) ECM-983A is stored if the engine control module (ECM) registers an internal fault indicating that the calculated engine speed (RPM) in the internal monitoring functions differs from the normal calculated engine speed (RPM) in the engine control functions. The diagnostic trouble code (DTC) is diagnosed with the engine running and at an engine speed (RPM) of more than 520 RPM.
Substitute Value
The engine speed (RPM) and torque are limited to a calculated normal operating range.
Possible Source
- Defective engine control module (ECM).
Fault symptom[s]
- Maximum engine speed (RPM) too low
- Cruise control does not function at all
- Uneven idle
- Malfunction indicator lamp (MIL) lit.