Case IH 3467 – Engine Control Unit (ECU): Water pump actuator reports an electrical error

The internal motor controller of the water pump detects an electrical fault—such as a short circuit to the battery, a short to ground, an open circuit, or an internal microcontroller failure.

• Case IH Magnum
• Case IH Steiger
• Case IH Optum
• Case IH Puma
• Case IH Axial-Flow

1. 1

   Inspect the wiring harness leading from the Engine ECU to the water pump actuator for chafing, melting, or rodent damage.

2. 2

   Disconnect the water pump actuator connector and check for water ingress, corrosion, or pushed-back pins.

3. 3

   Turn the key to the ON position and verify that the actuator is receiving proper supply voltage (12V or 24V) and has a solid ground.

4. 4

   Check the PWM/CAN communication wire between the ECU and the pump for continuity.

5. 5

   Check if the water pump pulley can be turned by hand (with the belt off) to ensure no mechanical binding or seized bearings are causing an electrical overdraw.

1. 1

   Prep the Machine

   Park the machine on a level surface, turn off the engine, and disconnect the main battery power switch.

2. 2

   Drain Coolant

   Place a clean drain pan under the radiator petcock and engine block drain. Drain the engine coolant. (If the coolant is relatively new and uncontaminated, it can be reused; otherwise, prepare to replace it).

3. 3

   Remove Drive Belt

   Use a breaker bar to release tension on the serpentine belt tensioner and slip the belt off the water pump pulley.

4. 4

   Disconnect Electrical

   Unplug the electrical harness connector from the water pump actuator.

5. 5

   Remove the Water Pump

   Remove the mounting bolts securing the water pump assembly to the engine block. Note the length and position of each bolt, as they may vary.

6. 6

   Clean Mating Surface

   Thoroughly clean the engine block mating surface, ensuring no old gasket material remains.

7. 7

   Install New Pump

   Install the new water pump and actuator assembly using a new OEM gasket. Torque the mounting bolts to the engine manufacturer's specifications in a crisscross pattern.

8. 8

   Reassembly

   Reinstall the serpentine belt and reconnect the electrical harness.

9. 9

   Refill and Bleed

   Refill the cooling system with the specified CNH coolant. Leave the radiator cap off temporarily, reconnect the battery, and start the engine. Let it idle to bleed trapped air from the cooling system. Top off the coolant as the thermostat opens.

10. 10

    Clear Codes

    Connect the CNH Electronic Service Tool (EST) to clear the inactive 3467 fault code and verify that the pump responds to ECU commands.