Kubota P2622 – Engine ECU (Engine Control Unit): Intake throttle lift sensor: High

The voltage signal from the intake throttle lift sensor is abnormally high (4.89 V or higher for 2.8 seconds or more), indicating a short circuit to the battery (+B) in the sensor or its wiring harness. This triggers a limp home mode that limits engine output to approximately 75%, forces the intake throttle 100% open, and illuminates the engine warning light.

• V3800-CR-TE4
• V3800-CR-TIE4
• V3307
• V2403-CR-TE4B
• 07-CR-E5 series
• SVL75
• SVL90-2
• SVL95-2
• SVL97-2
• M5-091
• M5-111
• M6-101
• M6-111
• Baroness mowers
• TL6 loaders

1. 1

   Verify Battery Voltage: Ensure the machine's battery voltage is normal (12V or higher).

2. 2

   Verify Sensor Supply Voltage: Check that the sensor supply voltage (VCC#) from the ECU is normal (typically a 5.00V reference signal).

3. 3

   Harness Inspection: Inspect the wiring harness between the Engine ECU and the Intake Throttle Valve for an open circuit or a short circuit to the power supply (+B).

1. 1

   Safety First

   Turn off the key switch and disconnect the negative battery cable to prevent electrical damage.

2. 2

   Locate the Component

   Locate the Intake Throttle Valve (Electronic Throttle Body) on the engine's intake manifold.

3. 3

   Test the Wiring

   Disconnect the connector at the throttle valve. Using a multimeter, test the harness pins back to the Engine ECU to rule out a short to power or an open wire.

4. 4

   Replace the Assembly

   If the wiring and ECU supply voltage test normal, the sensor itself has failed internally. You must replace the entire Intake Throttle Valve assembly.

5. 5

   Reassembly and Clearing

   Install the new throttle valve, reconnect the wiring harness, and reconnect the battery.

6. 6

   Verification

   Use a diagnostic tool (such as Kubota Diagmaster) to clear the DTCs. Start the engine and verify that the engine warning light remains off and full power is restored.