Case IH 11011 – Instrument Controller (INST): Fuel Level Sensor Signal Too Low

The transmission or instrument controller has detected that the fuel level sensor signal voltage is out of range on the low side (drops below 0.125 volts for more than 1 second), which typically points to an open circuit or a direct short to ground in the sensor or its circuit.

• MX Magnum
• STX Steiger
• Case IH MX Magnum Series
• Case IH TG Series
• Case IH Puma Series
• Case IH Steiger Series

1. 1

   Test Sensor Resistance: Disconnect the fuel level sensor and test its resistance with a multimeter. The resistance should scale linearly depending on the float position (e.g., on some 20 series models, Zone 0 is 5-10 Ohms, scaling up to 315-345 Ohms at Zone 3).

2. 2

   Inspect the Wiring Harness: Check the wiring harness running from the Instrumentation Controller (INST) to the fuel level sensor. Look for chafed wires causing a short to ground, or broken wires causing an open circuit.

3. 3

   Check the Controller: If the sensor and wiring harness both test within normal specifications, the fault may lie with a failed Instrument Controller.

1. 1

   Locate the Sensor

   Locate the fuel level sensor assembly mounted on the top or side of the main fuel tank.

2. 2

   Disconnect and Inspect

   Turn off the machine's battery disconnect. Unplug the wiring harness connector at the fuel level sensor. Inspect the pins for corrosion, moisture, or damage.

3. 3

   Measure Resistance

   Using a multimeter, measure the resistance across the sensor's terminals. If the reading is completely open (infinite resistance) or shorted (0 ohms), the sensor has failed internally.

4. 4

   Harness Continuity Test

   If the sensor tests good, perform a continuity test on the signal and return wires between the sensor connector and the Instrument Controller pins. Repair any broken wires or re-pin connectors that are shorting to the chassis.

5. 5

   Replace the Sensor

   If the sensor is faulty, clean the area around the mounting flange to prevent debris from entering the tank. Remove the mounting screws/lock ring, extract the old sensor and float arm, and install the new OEM sensor with a new gasket.

6. 6

   Clear Codes

   Reconnect the battery, turn the key to the ON position, and verify the fuel gauge registers correctly. Clear the inactive 11011 fault code from the instrument display.