Case IH t1A – Engine Controller / Engine ECU: Fuel Quantity Shut-Off, Shorted To High Source

The electrical circuit controlling the fuel quantity shut-off valve (solenoid) has a short circuit to a high voltage source (typically battery voltage), which prevents the engine controller from properly regulating or shutting off the fuel supply.

• MXM
• MX Series
• MX100
• MX110
• MX120
• MX135
• MX150
• MX170
• MX175
• TG Series
• Puma
• TM Series
• TM115-TM165
• MXM120-MXM155
• CX50-CX100
• MX80C-MX100C

1. 1

   Inspect connectors at the fuel shut-off solenoid and the Engine ECU for damaged, bent, or corroded pins

2. 2

   Inspect the wiring harness routing between the Engine ECU and the fuel shut-off solenoid for rubbed-through insulation or melted wires

3. 3

   Using a multimeter, test the signal wire for the fuel shut-off valve to see if it is receiving unintended battery voltage (shorted to high source) when disconnected

4. 4

   Test the internal coil of the fuel shut-off solenoid to determine if it is internally shorted to power

1. 1

   Turn off the tractor and disconnect the battery

   Turn off the tractor and disconnect the battery to prevent further electrical damage.

2. 2

   Locate the fuel quantity shut-off solenoid

   Locate the fuel quantity shut-off solenoid on the fuel injection pump.

3. 3

   Disconnect the electrical connector

   Disconnect the electrical connector from the solenoid.

4. 4

   Repair the damaged section of the harness

   If the diagnostic tests revealed a wiring issue, repair the damaged section of the harness using a harness repair kit, ensuring correct pin removal and insertion.

5. 5

   Remove the faulty fuel shut-off solenoid

   If the solenoid is internally shorted, unbolt and remove the faulty fuel shut-off solenoid from the injection pump.

6. 6

   Install the new fuel shut-off solenoid

   Install the new fuel shut-off solenoid (note: updated mounting bolts may be required depending on the specific part revision).

7. 7

   Reconnect the electrical connector and battery

   Reconnect the electrical connector, reconnect the battery, and clear the active fault codes.

8. 8

   Start the engine

   Start the engine to verify the repair and ensure the code does not return.