Case IH 3289 – Engine Control Module (ECM) / EDC: Turbo Compound Monitoring - Signal Low

The signal voltage returning from the turbo compound monitoring sensor has dropped below the minimum acceptable threshold. This indicates an electrical fault in its monitoring circuit, most commonly a short to ground, an open circuit, or a completely failed sensor.

• Case IH Magnum 235
• Case IH Magnum 260
• Case IH Magnum 290
• Case IH Magnum 315
• Case IH Magnum 340 (Series 4)
• Case IH Steiger series

1. 1

   Visually inspect the wiring harness between the Engine ECU and the turbo compound monitoring sensor for chafing, melted insulation, or breaks that could cause a short to ground.

2. 2

   Disconnect the sensor and the ECM to check the connector pins for corrosion, moisture ingress, or pushed-out pins.

3. 3

   Using a multimeter, verify the sensor supply voltage (typically 5V) and the ground circuit. Test the signal wire for continuity to the ECM and ensure it is not shorted to the chassis ground.

4. 4

   Look for related FPT 14E codes (such as 3287, 3288, or 3290) that might indicate a broader harness issue.

1. 1

   Power Down

   Turn off the machine and disconnect the battery to prevent electrical spikes while servicing the ECM and engine harness.

2. 2

   Harness Repair

   If the diagnostic tests revealed a short to ground or a broken wire in the signal circuit, repair the damaged section of the wiring harness or replace the harness segment.

3. 3

   Sensor Replacement

   If the wiring, supply voltage, and ground test within specification, the turbo compound monitoring sensor itself has failed internally. Disconnect the sensor pigtail.

4. 4

   Install Sensor

   Remove the faulty sensor from the turbo compound unit/housing and install the replacement sensor, tightening to OEM torque specifications.

5. 5

   Reassembly

   Reconnect the sensor harness and reconnect the battery.

6. 6

   Code Clearing

   Connect the CNH EASy diagnostic tool (or equivalent) to the machine's diagnostic port and clear the inactive 3289 fault code.

7. 7

   Verification

   Start the engine and run it under load to verify that the turbo compound monitoring signal is reading correctly and the fault code does not return.