Case IH 293 – ENG: Hydraulic Fan Hydraulic Oil Temperature Sensor Voltage is too high

The controller is detecting an open circuit (a broken wire or disconnected plug) or a short to a power source on the temperature sensor circuit.

• MX Magnum
• STX Steiger
• Magnum series
• Puma series
• Steiger series
• Maxxum series
• AFX series (e.g., AFX8010)

1. 1

   Inspect the wiring harness and connectors leading to the hydraulic fan hydraulic oil temperature sensor for physical damage, corrosion, or disconnected plugs.

2. 2

   Using a multimeter, check the sensor supply wiring for an open circuit or a short to power (e.g., check for continuity between the main frame harness connectors).

3. 3

   Test the sensor's resistance to see if it has failed internally (an open internal resistor will cause a high voltage reading at the ECU).

1. 1

   Power down machine

   Power down the machine and engage the parking brake.

2. 2

   Locate sensor

   Locate the hydraulic fan hydraulic oil temperature sensor on the hydraulic reservoir or hydraulic fan circuit block.

3. 3

   Inspect harness

   Disconnect the sensor harness and inspect the pins for pushed-out terminals or corrosion.

4. 4

   Repair wiring

   If the wiring harness is damaged (open circuit), repair the broken wire or replace the damaged connector.

5. 5

   Replace sensor

   If the wiring tests good, the sensor itself has failed open. Unthread the faulty sensor and install a replacement.

6. 6

   Verify repair

   Reconnect the harness, power on the machine, and clear the stored ENG fault codes to verify the repair.