Case IH 1 – Electronic Instrument Cluster (EIC): Engine Oil Pressure Sender Short or Open Circuit

The system is detecting an electrical fault—either a broken wire (open circuit), a short to ground, or a short to voltage—in the circuit for the engine oil pressure sender. Because of this electrical fault, the system cannot accurately monitor the engine oil pressure, which will typically trigger a critical stop alarm or warning light to prevent potential engine damage.

• MXM
• STX Series
• STX500
• Magnum Series
• Magnum 255
• MX210
• MX230
• TG210
• TG230
• Puma Series
• MX Series
• CX Series
• Axial-Flow Series

1. 1

   Turn the keystart to the OFF position.

2. 2

   Locate the engine oil pressure sender and disconnect its electrical connector (designated as connector C003).

3. 3

   Inspect the connector for pushed-out pins, corrosion, or damaged wires.

4. 4

   Bypass Test: Using a jumper wire, short the 'Signal Out' pin (wire FM–31–Y/S) to the '+5V' reference pin (wire FM–2014–G/K) on the harness side of connector C003.

5. 5

   Turn the key ON and observe the Electronic Instrument Cluster.

6. 6

   Evaluate: If Error Code 1 disappears and the oil pressure display indicates a reading, the wiring harness and the instrument cluster are functioning correctly, meaning the sender is faulty. If the code remains, the fault lies within the wiring harness or the instrument cluster itself.

1. 1

   Replace faulty sender

   If the sender is faulty: Ensure the engine is off and cooled down. Unplug the electrical connector from the oil pressure sender. Unthread the old sender from the engine block (have a rag ready to catch minor oil drips). Thread in the new OEM replacement sender and tighten to specification. Reconnect the electrical connector.

2. 2

   Test and repair wiring harness

   If the harness is faulty (code persisted during the bypass test): Perform a continuity test on the signal and 5V reference wires from connector C003 back to the Electronic Instrument Cluster. Check for shorts to ground or shorts to voltage along the harness routing. Repair any broken wires or chafed insulation found in the harness.

3. 3

   Repair or replace Electronic Instrument Cluster

   If the harness tests perfectly: The Electronic Instrument Cluster itself has an internal fault and will need to be repaired or replaced.

4. 4

   Verify repair

   Final Step: Clear the diagnostic memory and run the engine to verify that the oil pressure reads accurately and Error Code 1 does not return.