Case IH F-102-00 - ECU – Engine Control Unit (ECU): Intake manifold pressure sensor voltage is higher than expected

The Engine Control Unit (ECU) monitors the intake manifold pressure (boost pressure) and temperature via a combined MAP/IAT sensor. The analog-to-digital converter inside the ECU processes this voltage signal into a physical pressure value. If the voltage signal returned to the ECU exceeds the maximum expected threshold, this fault is triggered. This typically indicates a short circuit to a high voltage source, a failed sensor, or an internal ECU failure.

• MAGNUM AFS Connect
• Magnum
• Puma
• Maxxum (110-140)
• Steiger
• Farmall
• WorkMaster 50
• Axial-Flow 240 Series
• Axial-Flow 5130 through 9250 series
• Axial-Flow 7120
• Axial-Flow 7240
• Axial-Flow 8240
• Axial-Flow 9240

1. 1

   Check if the tractor battery has been connected to an external power supply (like a jump box or external charger). If connected, disconnect it and test the system for normal operation, as voltage spikes can trigger this code.

2. 2

   Visually inspect the intake manifold pressure sensor, the relevant wiring harnesses, and the ECU connectors for physical damage, bent pins, corrosion, or wire chafing that could cause a short to a high voltage source.

3. 3

   Check the ECU (e.g., module A-095) for the appropriate software version. If a known software bug exists for your specific model, re-flash the ECU.

4. 4

   Use the Electronic Service Tool (EST) / PT-Box to check the live status of the fault and verify the sensor's voltage readings.

1. 1

   Power Down

   Turn off the machine and disconnect the battery power supply.

2. 2

   Sensor Replacement

   Locate the Intake Manifold Pressure Sensor on the engine intake manifold. Disconnect the 4-pin wiring harness, remove the faulty sensor, and install the replacement sensor. Reconnect the harness.

3. 3

   Clear the Code

   Connect the Electronic Service Tool (EST) and erase the fault code.

4. 4

   Unlock Inducement

   Because this specific fault causes an engine inducement (an automatic reduction to low idle speed / power derate after 30 seconds to protect the engine), you must use the EST to perform the "Engine Restart Counter Reset / Unlock Inducement" configuration in the configure menu.

5. 5

   Test

   Return the machine to service and verify normal operation.