Case IH 3417 – Engine Controller (Engine ECU): Short Circuit In Glow Plugs - Cyl. 4

The system has detected an electrical short circuit on the specific circuit supplying power to the glow plug located in cylinder number 4.

• Farmall
• skid steer
• SR250
• TR270
• Farmall series (65A, 75A, 85C, 95C, 105C)
• JX series (JX60 through JX1095)
• Quantum series
• AVJ/VJ series

1. 1

   Check Fuses and Relays: Inspect the main glow plug fuse (e.g., F57 60A Glow plug fuse on Farmall models) and the Fast Glow Plug Control Unit (FGPCU) / Glow Relay output to ensure a short hasn't blown the circuit protection.

2. 2

   Inspect the Wiring Harness: Trace the wiring from the Engine ECU/Glow Plug Control Module to the cylinder 4 glow plug. Look for chafed insulation, melted wires, or areas where the wire might be shorting directly to the engine block/ground.

3. 3

   Test the Glow Plug: Carefully disconnect the electrical plug from the pencil-type glow plug on cylinder 4. Use a multimeter to measure the resistance of the glow plug itself. If it shows zero resistance (continuity to ground), the glow plug is internally shorted and must be replaced.

1. 1

   Disconnect Power

   Disconnect the negative battery cable to prevent accidental arcing or further electrical damage while working on the glow plug circuit.

2. 2

   Locate Cylinder 4

   Identify cylinder 4 on the engine block and locate its glow plug.

3. 3

   Disconnect Wiring

   Carefully disconnect the electrical connector/plug from the top of the pencil-type glow plug.

4. 4

   Remove the Faulty Plug

   Using an appropriately sized deep socket (often 24mm for these specific 1/2" BSP plugs), carefully unthread and remove the shorted glow plug from the cylinder head.

5. 5

   Install the New Plug

   Thread the new glow plug into the cylinder head by hand to prevent cross-threading, then tighten it to the manufacturer's specified torque.

6. 6

   Reconnect

   Reattach the electrical connector to the new glow plug.

7. 7

   Restore Power and Clear Codes

   Reconnect the battery. Turn the key switch to the ON position to allow the Engine ECU to cycle the glow plugs. Connect a diagnostic tool to clear code 3417 from the Engine Controller and verify the code does not return.