Kubota P0107 – ECM: MAP Sensor Circuit Low Voltage

The Manifold Absolute Pressure (MAP) sensor signal voltage has dropped below 0.050 volts for at least 1 second while the engine is cranking or running. This indicates an impossibly low pressure reading, typically caused by a sensor malfunction, an open circuit, or a short to ground in the sensor wiring harness. When this occurs, the ECM initiates a Power Derate 1 (limp mode) to protect the engine, affecting fuel delivery and ignition timing.

• WG972
• WG1603
• WG1605
• WG1903
• WG2503
• WG3800

1. 1

   Visually inspect the MAP sensor connector and wiring harness for melted wires, chafing, loose connections, or bent/corroded pins.

2. 2

   Inspect the vacuum hose connecting the sensor to the intake manifold for cracks, blockages, or a loose fit.

3. 3

   Verify the sensor is receiving a 5V reference voltage from the ECM and has a solid ground at the connector using a multimeter.

4. 4

   Measure the MAP signal voltage with the key ON and engine OFF (should be 2.0V to 2.8V depending on altitude).

5. 5

   Perform a vacuum pump test by applying vacuum to the sensor and observing if the signal voltage changes smoothly.

1. 1

   Disconnect Power

   Turn off the ignition and disconnect the negative battery terminal to prevent electrical shorts.

2. 2

   Locate the Sensor

   Locate the MAP sensor mounted directly on or near the intake manifold.

3. 3

   Remove the Sensor

   Press the release tab to unplug the electrical connector and remove the mounting screws or bolts.

4. 4

   Clean the Port

   Carefully pull the old sensor out, inspect the mounting port, and wipe away any carbon buildup or debris.

5. 5

   Install the New Part

   Insert the new MAP sensor into the port and secure it with mounting hardware without overtightening.

6. 6

   Reconnect

   Plug the electrical connector back in until it clicks securely and reconnect the negative battery terminal.

7. 7

   Clear Codes

   Connect a diagnostic scan tool to clear the P0107 fault code from the ECM.

8. 8

   Test Drive

   Start the engine, verify smooth idle, and perform a test drive under load to ensure the code does not return.