Diagnostic trouble code (DTC) information

Condition 

Fig 1: Identifying Engine Control Module

Courtesy of VOLVO CARS OF NORTH AMERICA.

Diagnostic trouble code (DTC) ECM-9100 is stored if the engine control module (ECM) registers an internal fault or a fault in the circuit for the damper motor in the throttle unit when the ignition is switched on.

Substitute Value 

The engine control module (ECM) shuts down the supply to the throttle unit damper motor. The throttle will set itself to the return position.

Possible Source 

• Contact resistance or oxidation in the terminals between the engine control module (ECM) and the throttle unit
• Open-circuit, short-circuit to ground or short-circuit to supply voltage in the wiring for the damper motor in the throttle unit
• Short-circuit to each other in the wiring for the damper motor in the throttle unit
• Defective throttle unit
• Defective engine control module (ECM).

Fault symptom[s] 

• Malfunction indicator lamp (MIL) lit
• Poor performance.