Case IH 3696 – Engine Control Unit (ECU): Glow Plugs: Array of DFCs for Failure in Cylinder 2 Glow Plug

The engine control system has detected an electrical fault—such as an open circuit (burnt-out element), a short to ground, or a short to battery—in the glow plug circuit specifically for Cylinder 2. This prevents the cylinder from receiving proper pre-heating, which can lead to hard starting or rough idling in cold conditions.

• Farmall series
• JX series
• Steiger
• SR250
• SV250

1. 1

   Perform a resistance test by disconnecting the electrical connector at the Cylinder 2 glow plug and measuring resistance to ground (should be under 2 ohms; infinite/OL means burnt out).

2. 2

   Inspect the wiring harness from the Glow Plug Control Unit / Engine ECU to the Cylinder 2 glow plug for chafing, corrosion, pinched wires, continuity, and shorts to ground or battery.

3. 3

   Perform a voltage test with the glow plug disconnected by turning the ignition key to the 'ON' position (pre-heat phase) to verify the Glow Plug Control Unit is sending correct voltage.

1. 1

   Disconnect Power

   Disconnect the negative battery cable to prevent accidental shorts.

2. 2

   Locate the Component

   Locate the glow plug for Cylinder 2 on the engine cylinder head.

3. 3

   Remove the Harness

   Carefully unclip or unbolt the electrical connector/wire from 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 to prevent dirt or debris from falling into the open cylinder.

5. 5

   Remove the Glow Plug

   Using a deep socket, carefully unscrew the faulty glow plug. Note: Do not force it if it is stuck, as breaking a glow plug in the cylinder head requires extensive extraction work.

6. 6

   Install the New Part

   Thread the new glow plug in by hand to ensure it does not cross-thread. Tighten it to the specific OEM torque specification for your engine model.

7. 7

   Reconnect

   Reattach the electrical connector to the new glow plug.

8. 8

   Clear Codes

   Reconnect the battery. Turn the ignition on to cycle the glow plug system, then use a diagnostic service tool to clear the 3696 fault code from the Engine ECU.