Case IH 3164 – Engine ECU (Electronic Control Unit A-095): Fan speed above maximum threshold

The Electronic Control Unit (ECU) monitors the fan speed sensor (designated as Z-008) to determine the fan's rotational speed. The speed is measured using the time interval between pulses. If the ECU determines that the fan speed is operating above the maximum allowed threshold relative to the current engine speed, it will log this fault code.

• Steiger T4B
• 240 Series Axial-Flow Combines (7230, 7240, 8240, 9240)
• Case IH Puma series
• Case IH Magnum series (MX180, MX200, MX210, MX220, MX230, MX240, MX255, MX270, MX285, Magnum 235-380)

1. 1

   Verify if any other error codes are displayed. If no other codes are active, proceed to the next step.

2. 2

   Ensure the tractor/machine battery power supply has not been connected to an external power supply (like a jump starter). If connected, disconnect it and test the system for normal operation.

3. 3

   Check the battery voltage on the instrument cluster. Start the engine and run it at 2000 RPM to ensure the charging system is operating normally.

4. 4

   Test the fan clutch operation: With the engine running, unplug the fan connector (X-811). The viscous fan should default to full lock-up. If it does not lock up, the fan clutch itself is likely mechanically failed.

1. 1

   Inspect Wiring

   Check the wiring harness between the ECU (A-095), the fan speed sensor (Z-008), and the fan clutch solenoid (X-811) for any shorts to ground, shorts to battery voltage, or open load errors.

2. 2

   Test the Sensor

   If the fan locked up successfully during the diagnostic check but the code persists, the fan speed sensor (Z-008) may be sending erratic or incorrect pulse intervals to the ECU. Inspect the sensor for damage or debris and replace it if it fails continuity/resistance checks.

3. 3

   Replace the Fan Clutch

   If the fan failed to lock up when connector X-811 was unplugged during the diagnostic phase, the viscous fan clutch assembly has failed internally and must be replaced.

4. 4

   Clear Codes

   After replacing the faulty component, clear the inactive codes from the ECU and run the engine to verify the fan speed stays within the maximum threshold.