Massey Ferguson E723.31 – Engine Control Unit (ECU) / EEM3 or EEM4: Camshaft Speed Sensor Signal Missing / No Signal

The engine control system has not been able to detect any signal from the camshaft speed sensor. When this signal is missing, the engine may take a significantly longer time to start because the system must rely solely on the crankshaft speed sensor to determine Top Dead Center, or the engine may fail to start altogether.

• 7616
• 5612
• 7622
• Interim Tier 4 (2012-2015)
• 7614
• 5611
• 7615
• 5610
• 5613
• 7620
• 5609
• 7618
• 5608
• 7619
• 7626
• 7624
• 4707
• 4708
• 4709
• 4710
• 5400 series
• 5710SL - 5713SL
• 6400
• 6485
• 6490
• 6495
• 6497
• 6499
• 7400
• 7485
• 7490
• 7495
• 7714 through 7726S
• 8400
• 8450
• 8460
• 8470
• 8480
• 7256 Combine Harvester
• MF 9305 Telescopic Handler

1. 1

   Check the sensor wiring harness for defects, including broken wires, short circuits to battery/earth, or reversed signal lines.

2. 2

   Ensure the sensor is properly connected and that the pins inside the connector are not corroded or pushed out.

3. 3

   Verify if there are accompanying codes (e.g., SPN 723 FMI 8) indicating that the camshaft and crankshaft signals are out of phase due to rapid engine speed changes, rough running, or mechanical defects.

4. 4

   Inspect the trigger wheel (the toothed wheel on the camshaft that the sensor reads) for physical damage.

5. 5

   If the wiring, sensor, and trigger wheel are all in good condition, verify if the engine control unit (ECU) is defective.

1. 1

   Locate the sensor

   Ensure the machine is turned off and the battery is disconnected. Locate the camshaft speed sensor on the engine block, typically mounted near the timing gear or front case.

2. 2

   Disconnect and remove

   Unplug the electrical connector from the sensor. Remove the retaining bolt(s) securing the sensor to the engine block and carefully pull the sensor out.

3. 3

   Inspect mounting hole

   Look into the mounting hole to ensure the trigger wheel is intact and free of debris.

4. 4

   Install new sensor

   Insert the new OEM camshaft speed sensor into the port. Secure it with the retaining bolt, applying standard threadlock if specified by the manual.

5. 5

   Reconnect wiring

   Plug the electrical connector back into the sensor, ensuring it clicks into place.

6. 6

   Clear fault codes

   Reconnect the battery. Use the AGCO Electronic Diagnostic Tool (WinEEM3/WinEEM4 Service Tool) to clear the stored E723.31 fault code from the ECU memory, or use the dash diagnostic button sequence by holding the diagnostic button while cycling the ignition.