New Holland ENG 3672 – Engine Control Module (Engine ECU): EGR Short to Ground on EGR Out2 pin A35 error for H-bridge

The control module has detected a short circuit to ground on the specific control circuit (Pin A35) that drives the H-bridge power stage for the Exhaust Gas Recirculation (EGR) valve actuator.

• F5C engine
• F5H engine
• L220
• L230
• SR175
• B90B
• B100B
• Compact Track Loaders
• T4 series
• T5 series

1. 1

   Verify the vehicle's electrical system for high voltage fluctuations, which can sometimes trigger H-bridge errors.

2. 2

   Locate the 60-pin connector (Connector A) at the Engine ECU and trace the wire from Pin A35 to the EGR valve actuator.

3. 3

   Inspect the entire length of the harness for chafing, melting, or pinched areas where the wire might be shorting against the engine block or chassis.

4. 4

   Disconnect the electrical connector at the EGR valve and use a multimeter to check for continuity to ground on the Pin A35 circuit. If grounded, the short is in the harness; if not, the short is internal to the EGR valve actuator's electronic control unit.

1. 1

   Disconnect Power

   Turn off the machine and disconnect the negative battery cable.

2. 2

   Wiring Repair

   If the diagnostic tests proved the harness is shorted, repair the damaged section of the wire or replace the engine wiring harness.

3. 3

   EGR Valve Replacement

   If the short is internal to the EGR valve: Drain the engine coolant. Remove the water hoses connected to the EGR unit. Unscrew the fastening screws on the front side and the valve support side. Remove the faulty EGR valve/actuator assembly. Install the new EGR valve, torque the fastening screws to OEM spec, and reconnect the coolant hoses and electrical connector. Refill and bleed the engine coolant system.

4. 4

   System Reset

   Reconnect the battery. You must use the New Holland Electronic Service Tool (EST) to clear the fault codes and run the appropriate service tool procedure to restore the self-learning parameters for the new EGR valve.