Massey Ferguson 9304 – EEM3: Vehicle Speed Missing

The Engine Electronic Module (EEM3) is not receiving the vehicle speed signal from the CAN bus, triggering a timeout after 5000ms. This indicates an incorrect CAN signal or improper velocity source selection. The loss of speed data can result in a reduction of engine power and speed, and will affect the operation of other tractor systems that rely on vehicle speed information.

• 8600 Series
• 5400 Series
• 6400 Series
• 7600 Series
• 3000 Series
• 3100 Series
• 3600 Series
• 6100 Series
• 6200 Series
• 7400 Series
• 6600 Series
• 6700 Series
• 7700 Series
• 8400 Series
• 32
• 34
• 38
• 7256

1. 1

   Cycle the ignition off and on to see if the fault clears on restart

2. 2

   Use a diagnostic tool to check for other active fault codes, particularly related to the CAN bus or other sensors that might trigger this code

3. 3

   Visually inspect the vehicle speed sensor and wiring harness for physical damage, cracks on the sensor body, frayed wires, or burnt sections

4. 4

   Inspect the electrical connector for bent, corroded, or pushed-back pins

5. 5

   With the sensor disconnected, perform a continuity test on the ground and signal wires of the harness

6. 6

   Check the wiring harness for any short circuits

7. 7

   With the ignition off and sensor disconnected, measure the sensor's resistance (expected value is approximately 450 ohms +/- 20 ohms for certain sensors)

1. 1

   Locate the Vehicle Speed Sensor

   The vehicle speed sensor is typically located on the transmission or final drive housing, where it can read the rotational speed of a gear or shaft.

2. 2

   Disconnect and Remove

   Disconnect the electrical connector from the sensor. Then, unscrew and remove the sensor from its mounting position.

3. 3

   Install the New Sensor

   Apply a small amount of a suitable sealant, such as Loctite 5922, to the threads of the new sensor.

4. 4

   Set the Air Gap

   Screw the sensor in by hand until it makes contact with the gear it is reading. Then, unscrew it by 3/4 of a turn to set the correct air gap.

5. 5

   Tighten and Reconnect

   Tighten the counter-nut to the specified torque, which is approximately 6 Nm for some models. Reconnect the electrical connector.

6. 6

   Clear Fault Codes

   Use a diagnostic tool to clear the 9304 fault code and any other related codes.

7. 7

   Verify the Repair

   Operate the tractor to ensure the fault code does not return and that all systems that rely on vehicle speed are functioning correctly.