Case IH 3695 – Engine Control Unit (ECU) / Electronic Diesel Control (EDC): Failure in glow plug cylinder 1

The system has detected an electrical fault, such as an open circuit, short circuit, or abnormal resistance, in the pre-heat glow plug specifically located at engine cylinder 1.

• skid steer
• SR220
• SR240
• SR250
• 410
• 420
• TR270
• 420CT
• Farmall 65A
• Farmall 75A
• Farmall 105A
• JX60
• JX95

1. 1

   Inspect the wiring harness and electrical connector leading to the cylinder 1 glow plug (typically the front-most cylinder on the engine block) for chafing, corrosion, or disconnection.

2. 2

   Disconnect the electrical lead to the cylinder 1 glow plug and measure the resistance of the plug using a multimeter (checking between the plug terminal and the engine block ground). An open circuit (infinite resistance) or a dead short indicates a failed glow plug.

3. 3

   With the wire disconnected, cycle the ignition to the 'ON' position (triggering the cold-start pre-heat phase) and measure the voltage at the harness connector. It should receive battery voltage from the Fast Glow Plug Control Unit (FGPCU). If there is no voltage, the issue may lie in the wiring harness, a blown fuse, or the control module itself.

1. 1

   Disconnect Power

   Disconnect the negative battery cable to prevent accidental electrical shorts.

2. 2

   Access the Plug

   Locate the glow plug on cylinder 1. Remove any engine covers or brackets that may be obstructing access.

3. 3

   Disconnect Wiring

   Carefully remove the electrical connector or retaining nut securing the wire to the top of the glow plug.

4. 4

   Clean the Area

   Thoroughly clean the area around the base of the glow plug using compressed air or a brush. This is critical to prevent dirt and debris from falling into the open combustion chamber when the plug is removed.

5. 5

   Remove the Glow Plug

   Using a deep socket, carefully unscrew the faulty glow plug from the cylinder head. Note: If the plug is seized, apply penetrating oil and allow it to soak to prevent snapping the plug inside the head.

6. 6

   Install the New Part

   Thread the new glow plug into the cylinder head by hand to ensure it does not cross-thread. Tighten it to the OEM torque specification found in your specific machine's service manual.

7. 7

   Reassemble

   Reattach the electrical wire/connector to the new glow plug.

8. 8

   Clear Codes

   Reconnect the battery. Use the Electronic Service Tool (EST) to clear the 3695 fault code, cycle the ignition to trigger the pre-heat system, and verify the code does not return.