Case IH F-1136-00 - ECU – Engine Control Unit (ECU): ECU temperature sensor voltage is higher than expected

The signal voltage from the internal ECU temperature sensor has exceeded the maximum allowable threshold, indicating an open circuit or a short to a high voltage source. This can cause the engine to fuel incorrectly, mis-time, or trigger protective power derates (including 30-second emergency restarts).

• MAGNUM AFS Connect
• Case IH Magnum Series (180, 200, 220, 240, 250, 280, 310, 340, 380, 400)
• Case IH Steiger Series (370, 420, 470, 500, 620)
• Case IH 240 Series Axial-Flow Combines
• Case IH Austoft Sugar Cane Harvesters (A8000, A8800, 9900)

1. 1

   Check ECU Power and Grounds: Verify that the main power and ground cables to the Engine ECU are clean and tight to rule out a floating ground causing internal 5V reference circuits to spike.

2. 2

   Inspect ECU Connectors: Disconnect the main harnesses at the ECU and check for water ingress, corrosion, or bent pins that could bridge battery voltage to sensor circuits.

3. 3

   Monitor Live Data: Use the dealer service tool (EST) to view the 'ECU Internal Temperature.' If the value is stuck at an implausible extreme (e.g., -40°C or a default maximum) and does not change, the internal sensor is confirmed dead.

1. 1

   Turn off the machine and disconnect the main battery switch.

   This prevents electrical arcing during the repair.

2. 2

   Locate the Engine ECU.

   Typically mounted on the side of the engine block, utilizing vibration-isolating rubber mounts.

3. 3

   Carefully release the locking levers on the ECU wiring harness connectors and unplug them.

4. 4

   Remove the mounting bolts and remove the faulty ECU.

5. 5

   Install the replacement or remanufactured ECU and torque the mounting bolts to OEM spec.

6. 6

   Reconnect the wiring harnesses.

   Ensure the locking levers click fully into place.

7. 7

   Reconnect the battery.

8. 8

   Program the new ECU using the Case IH Electronic Service Tool (EST).

   Flash the correct engine dataset and write the specific Quick Response (QR) Injector Codes to the new ECU.

9. 9

   Clear the F-1136-00 fault code and run the engine to verify the repair.