New Holland 3667 – ECU: EGR Open Load Error

The Engine Control Unit (ECU) has detected an open circuit in the drive circuit for the Exhaust Gas Recirculation (EGR) valve. This indicates a loss of electrical connection to the EGR valve's power stage, preventing the ECU from controlling the component. The underlying condition is an electrical problem within the EGR valve actuator circuit, which disrupts proper exhaust gas recirculation operation.

• 580N T4
• 580SN T4
• 580SN WT T4
• 590SN T4
• C185
• L180
• L185
• C334
• C345
• C362
• TR340B
• TV450B
• TV620B
• W50BTC
• W60BTC
• W70BTC
• W80BTC

1. 1

   Use an Electronic Service Tool (EST) to verify the fault is active, note occurrences and engine hours, and attempt to clear it.

2. 2

   Visually inspect the wiring harness and connectors between the ECU and the EGR valve for chafing, corrosion, abrasion, or improper routing.

3. 3

   Disconnect the ECU and EGR valve connectors and measure the resistance of each wire in the harness (should be less than 10 ohms). Wiggle the harness during measurement to detect intermittent open circuits.

4. 4

   Measure the resistance from each wire to the chassis ground to check for a short to ground (should be greater than 20,000 ohms).

5. 5

   Disconnect the EGR valve connector and measure the resistance through the EGR valve's motor windings (should be less than 100 ohms). Infinite resistance indicates the internal motor has failed.

1. 1

   Disconnect battery

   Disconnect the negative terminal of the battery to prevent electrical hazards.

2. 2

   Remove EGR valve

   Locate the EGR valve between the exhaust and intake manifolds. Remove any obstructing components for access, then use a socket wrench to remove the mounting bolts and take off the valve.

3. 3

   Clean mounting surfaces

   Remove the old gasket. Thoroughly clean the mounting surfaces on both the engine and connecting pipes using a gasket scraper and wire brush to remove all carbon buildup and old gasket material.

4. 4

   Install new EGR valve

   Place a new gasket onto the clean mounting surface. Position the new EGR valve, hand-tighten the mounting bolts, and torque them to the manufacturer's specified value in a crisscross pattern.

5. 5

   Reassemble and reconnect

   Reinstall any components removed for access. Reconnect the EGR valve's electrical connector and the negative battery terminal.

6. 6

   Clear codes and perform relearn

   Reconnect the Electronic Service Tool (EST). Clear fault code 3667 and run the EGR valve relearn or calibration procedure to allow the ECU to recognize the new valve's operational parameters.

7. 7

   Verify repair

   Start the engine and operate the machine to confirm that the fault code does not return and the engine runs smoothly.