Deutz-Fahr M150 – Engine ECU (EMR - Electronic Motor Regulator): Charge Air Temperature Sensor Defective

Fault code M150 triggers when the Charge Air Temperature Sensor is defective, most commonly due to a short circuit to ground (KS GND) or when the sensor reads a value outside the normal operational range (e.g., intake air temperature too high or an implausible reading).

• FARMotion KD/KE engines
• TCD series engines
• Series 5 tractors
• Agrotron models

1. 1

   Inspect the wiring harness between the Charge Air Temperature Sensor and the Engine ECU (EMR) for chafed wires causing a short circuit to ground or a cable break

2. 2

   Disconnect the sensor and inspect the connector pins for corrosion, moisture, or bent terminals

3. 3

   With the ignition on, check the connector for the 5V reference voltage and a good ground supplied by the ECU

4. 4

   If the sensor is reading an actual over-temperature condition, verify that the charge air cooler (intercooler) is not blocked by debris and that the EGR valve is functioning correctly

5. 5

   Use the Deutz SERDIA diagnostic tool to read the live charge air temperature. If it reads a default extreme value (-40°C or +150°C), the sensor or circuit is definitively failed

1. 1

   Turn off the tractor, remove the key, and disconnect the negative battery terminal

   This prevents electrical spikes.

2. 2

   Locate the Charge Air Temperature Sensor

   It is typically threaded into the intake manifold or the charge air cooler downstream piping.

3. 3

   Disconnect the electrical harness from the sensor

   Depress the locking tab and disconnect the electrical harness.

4. 4

   Repair the wiring harness if damaged

   If the wiring harness was found to be damaged during diagnostics, repair the affected section using an approved Deutz cable repair kit.

5. 5

   Remove the defective sensor

   If the wiring is intact, use a wrench to carefully unthread and remove the defective sensor.

6. 6

   Install the new OEM Charge Air Temperature Sensor

   Tighten it to the specified torque (do not overtighten, as the manifold threads can be damaged).

7. 7

   Reconnect the electrical harness

   Ensure it clicks securely into place.

8. 8

   Reconnect the battery

9. 9

   Clear the fault codes

   Connect the SERDIA diagnostic tool (or equivalent scanner), turn the ignition on, and clear the M150 / SPN 105 fault codes from the EMR memory.

10. 10

    Start the engine and verify the repair

    Monitor the live charge air temperature data to confirm the repair is successful.