Diagnostic Trouble Code (DTC) Information ECM-9100

Condition 

Fig 1: Identifying Internal Atmospheric Pressure Sensor

Courtesy of VOLVO CARS OF NORTH AMERICA.

The diagnostic trouble code (DTC) is stored if the engine control module (ECM) registers an internal fault or a fault in the circuit for the throttle unit damper motor.

The diagnostic trouble code (DTC) is diagnosed when the engine is idling.

Substitute Value 

The engine control module (ECM) shuts down the supply to the damper motor for the electronic throttle unit. 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 electronic 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
• Damaged throttle unit
• Damaged engine control module (ECM).

Fault symptom[s] 

• Malfunction indicator lamp (MIL) lit
• Deterioration in performance
• Uneven idle.