Massey Ferguson 00.00.38 – Dash: Signal Voltage From Engine Speed Sensor Is Too High (Dash)

This code indicates that the voltage signal returning from the engine speed sensor (which monitors crankshaft RPM) is exceeding the expected maximum threshold. This is typically caused by a short circuit to power (+12V) in the sensor wiring, a failed internal sensor component, or severe connector contamination.

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• 7714S
• 7719S
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626
• 5710SL
• 5711SL
• 5712SL
• 5713SL
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 4707
• 4708
• 4709
• 4710
• 3600 Series
• 5400 Series
• 6400 Series
• 6700S Series
• 8400 Series
• 8700 Series

1. 1

   Inspect the engine speed sensor wiring harness for chafing, rubbing on the frame, or melted insulation that could cause a short to power (+12V)

2. 2

   Disconnect the sensor and check the connector pins for dust, moisture, or corrosion, which can bridge connections

3. 3

   Use Massey Ferguson's Wintest software or a compatible scan tool to monitor the live engine speed signal voltage before replacing the sensor

4. 4

   Ensure the sensor is seated correctly and the gap between the sensor and the flywheel/crankshaft reluctor wheel is within factory specification

1. 1

   Preparation

   Turn off the tractor, remove the key, and disconnect the negative battery terminal to prevent electrical spikes.

2. 2

   Access the Sensor

   Locate the engine speed sensor on the engine block (flywheel housing or timing cover). Depending on the model (e.g., MF 6499), you may need to remove a tire or access panels to reach the sensor.

3. 3

   Removal

   Clean the area around the sensor to prevent dirt from falling into the engine. Unplug the electrical connector. Remove the retaining bolt(s) and carefully pull the sensor out of its bore.

4. 4

   Installation

   Lubricate the O-ring on the new sensor (if applicable) and insert it into the housing. Install and tighten the retaining bolt.

5. 5

   Reconnection

   Plug the wiring harness back into the sensor, ensuring it clicks into place. Reconnect the battery.

6. 6

   Clear Codes

   Turn the ignition on. Navigate to the diagnostic menu on the dash and select the "Clear Codes" or "Reset Codes" option to clear 00.00.38 from the system. Start the engine and verify the tachometer works and the code does not return.