Diagnostic trouble code (DTC) information ECM-9990

Condition 

Fig 1: Identifying Engine Control Module

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The Engine Control Module (ECM) continuously checks its own internal reset functionality. The Diagnostic Trouble Code (DTC) is stored if there is a fault in the reset function.

The Diagnostic Trouble Code (DTC) can be diagnosed when the ignition is switched on.

Substitute Value 

• The Engine Control Module (ECM) attempts to reset itself.

Possible Source 

• Faulty software in the Engine Control Module (ECM)
• Damaged Engine Control Module (ECM).

Fault symptom[s] 

• Malfunction indicator lamp (MIL) lit
• The malfunction indicator lamp (MIL) flashes
• The engine cuts out
• The starter motor turns but the engine does not start.