Case IH 3165 (DTC 2B33) - ECU – Electronic Control Unit (ECU) A-095: Fan speed below minimum threshold

The Electronic Control Unit (ECU) monitors the fan speed sensor (designated as Z-008) to determine the fan's speed, which is measured using the time interval between electrical pulses. If the ECU determines that the fan speed has dropped below the minimum allowable threshold relative to the current engine speed, it logs this fault. The primary failure modes causing this condition include a physically blocked or inoperative cooling fan, a faulty vistronic fan clutch solenoid (Z-008), or damaged wiring.

• MAXXUM T4E
• Puma Series Tractors (e.g., Puma 125)
• 240 Series Axial-Flow Combines (e.g., 7230, 8230, 9230)
• Austoft Sugar Cane Harvesters (A8000, A8800, A8810, A9900)

1. 1

   Connect the Electronic Service Tool (EST) to check if the fault code is active or intermittent

2. 2

   Inspect the cooling fan for physical blockages or mechanical failure that would render it inoperative

3. 3

   Inspect the wiring harness and connections leading to the vistronic fan clutch solenoid (Z-008) and the fan speed sensor for shorts or open circuits

4. 4

   Check the battery voltage on the instrument cluster with the engine running at 2000 rev/min to ensure the charging system is providing adequate power to the ECU and sensors

1. 1

   Use the EST to confirm the fault is active.

2. 2

   Clear any debris or obstructions blocking the cooling fan.

3. 3

   Repair or replace any damaged wiring in the harness connecting to the Z-008 fan speed sensor or vistronic fan clutch solenoid.

4. 4

   If the wiring is intact but the fan speed is still reading incorrectly, replace the fan speed sensor or the vistronic fan clutch solenoid.

5. 5

   If the mechanical and sensor components are functioning properly, the issue may lie with the ECU A-095 software. Attempt to reinstall/reflash the ECU A-095 software.

6. 6

   If the ECU A-095 software cannot be reinstalled or the module is internally faulty, replace the ECU A-095.