Case IH 19200 (F-2630-02) - ECU – Engine Control Unit (ECU) / Vehicle Control Module (VCM): Plausibility check error of the forth fresh air temperature sensor at cold start

During a cold start (after the machine has been turned off long enough for a 'cold soak'), the control module compares the readings of various engine temperature sensors. If the 'fourth fresh air temperature sensor' deviates significantly from the other sensors, the system flags the reading as implausible and logs this fault code.

• VESTRUM CVX
• Case IH Magnum AFS Connect series tractors (e.g., Magnum 400)
• Case N-Series TLBs (Tractor Loader Backhoes)
• Other Case IH / New Holland high-horsepower tractors and equipment sharing this engine architecture

1. 1

   Verify Cold Soak: Ensure the machine has been turned off for at least 8–12 hours so that all engine fluids and components have equalized to the ambient outside temperature.

2. 2

   Live Data Comparison: Connect the Case IH Electronic Service Tool (EST). Before starting the engine, monitor the live data for all temperature sensors (Coolant Temp, Oil Temp, Intake Manifold Temp, and Fresh Air/Ambient Air Temp).

3. 3

   Identify the Outlier: Identify the specific fresh air temperature sensor that is reading out of range compared to the others (e.g., reading extremely high or extremely low compared to the actual outside temperature).

4. 4

   Circuit Inspection: Inspect the wiring harness and connector going to the faulty fresh air temperature sensor. Look for chafed wires, corrosion in the pins, or an open/short circuit.

5. 5

   Resistance Test: Disconnect the sensor and measure its resistance with a multimeter. Compare the reading against the OEM specification for the current ambient temperature to confirm if the sensor itself has failed internally.

1. 1

   Disconnect power

   Turn off the ignition and disconnect the battery master switch to prevent electrical shorts.

2. 2

   Locate sensor

   Locate the faulty fresh air temperature sensor (typically mounted near the air intake housing, air cleaner assembly, or EGR intake tract, depending on the specific engine layout).

3. 3

   Disconnect harness

   Depress the locking tab and disconnect the electrical harness connector from the sensor.

4. 4

   Remove sensor

   Unthread or unclip the faulty sensor from its mounting location.

5. 5

   Install new sensor

   Install the new replacement sensor and tighten it to the OEM torque specification (do not overtighten plastic-threaded sensors).

6. 6

   Reconnect harness

   Reconnect the electrical harness connector, ensuring it clicks securely into place.

7. 7

   Restore power

   Turn on the battery master switch and ignition.

8. 8

   Clear fault code

   Use the diagnostic service tool to clear fault code 19200 (F-2630-02).

9. 9

   Verify repair

   Verify the repair by checking the live data to ensure the new sensor is now reading the correct ambient temperature.