Case IH 271 – Engine Control Module (ECM): Front Pumping Control Valve current is low during 'click test' (open circuit)

The Engine Control Module (ECM) detects low or no electrical current on the front pumping control valve return circuit (specifically at ECM Pin 21) during a self-diagnostic 'click test'. This indicates an open circuit, typically caused by a broken wire, a disconnected or corroded harness connector, or an internally failed solenoid coil.

• MX Magnum
• STX Steiger
• MX Magnum Series Tractors
• TG Series Tractors

1. 1

   Disconnect the engine harness from the front pumping control valve at the four-pin connector and inspect for bent, broken, pushed back, expanded, or corroded pins.

2. 2

   Look for moisture in or on the connector and ensure the weather seals are not missing or damaged.

3. 3

   Test the wiring harness for continuity between the ECM (Pin 21) and the valve connector to rule out a broken wire or a short in the harness.

4. 4

   Measure the resistance of the front pumping control valve coil itself to determine if the solenoid has failed internally (open coil).

1. 1

   Disconnect power

   Turn off the key switch and disconnect the battery to prevent electrical shorts.

2. 2

   Repair wiring or connections

   If the diagnostic checks reveal damaged pins, moisture, or broken wiring in the harness, clean the connections, replace the damaged pins, or repair the wiring harness as necessary.

3. 3

   Replace front pumping control valve

   If the wiring is intact but the valve coil has an open circuit, the front pumping control valve must be replaced. Depending on the specific pump revision, you may need to replace the individual valve stator or the entire Accumulator Module assembly (refer to Cummins Procedure 005-085).

4. 4

   Reassemble and restore power

   Install the new component, reconnect the four-pin harness, and restore battery power.

5. 5

   Verify repair

   Clear the fault codes and cycle the key to allow the ECM to perform the 'click test' again to verify the repair.