Diagnostic trouble code (DTC) information ECM-500D

Condition 

Fig 1: Identifying Engine Speed (RPM) Sensor

Courtesy of VOLVO CARS OF NORTH AMERICA.

The engine control module (ECM) counts the number of teeth on the flywheel using the signal for the engine speed (RPM) sensor. The diagnostic trouble code (DTC) is stored if the engine control module (ECM) detects at least one tooth too few during a certain number of engine revolutions. The diagnostic trouble code (DTC) can be diagnosed when the engine is running.

Substitute Value 

• The control module uses the signal from the camshaft position (CMP) sensor if the camshaft position (CMP) sensor has been adapted
• Variable valve timing control is blocked.

Possible Source 

• Signal interference
• Incorrectly installed engine speed (RPM) sensor
• Damaged flywheel or ring gear.

Fault symptom[s] 

• The engine is difficult to start
• Poor performance.