Checking the wiring and components

Check the engine speed (RPM) sensor resistance. The resistance must be between 250-350 Ω.

Check the signal cables between engine control module (ECM) terminals #24 and #54 and engine speed (RPM) sensor terminals #1 and #2. Check for a short-circuit to ground or supply voltage, for a short-circuit to each other or an open-circuit according to Open-circuit, permanent faults . Remedy if necessary.

HINT: With the ignition on, the voltage between engine speed (RPM) sensor connector terminals #1 and #2 must be approximately 1.8 V with the reading taken at the ground terminal. 

Other information 

• To connect the breakout box, see Connecting the breakout box. EMS 2000 .

Fig 1: Identifying Engine Speed (RPM) Sensor Connector Terminals

Courtesy of VOLVO CARS OF NORTH AMERICA.

Fig 2: Identifying Ohmmeter

Courtesy of VOLVO CARS OF NORTH AMERICA.

Fig 3: Identifying EMS2000

Courtesy of VOLVO CARS OF NORTH AMERICA.

Was a fault found in the above fault-tracing? 

• YES 

  Refer to Verification 

• NO 

  Refer to Defective engine speed (RPM) sensor