New Holland 15553 – Steering Controller / TMF: Pump Driver Relay Open Circuit

The monitoring system has detected a break in the electrical circuit of the pump drive relay. This open circuit condition prevents the relay from being energized, which inhibits the function of the pump it controls. The system's self-diagnostics have identified that the electrical path to or through the relay is incomplete.

• T7 Series
• T7.235
• T8 Series
• T8010
• T8020
• T8030
• T8040
• T8050

1. 1

   Inspect all related fuses in the cab and engine compartment fuse boxes (on T8010-T8050 models, check the fuse and relay box located to the rear of the operator's seat)

2. 2

   Visually inspect the wiring harness and connectors associated with the steering control system for visible damage, corrosion, or loose connections

3. 3

   Use a multimeter to check for voltage at the control side of the relay to determine if the control signal from the module is present

4. 4

   Perform a continuity test on the wiring between the control module and the pump driver relay to identify any breaks in the circuit

5. 5

   Swap the suspect relay with a known good relay of the same type to see if the fault code clears

1. 1

   Locate the Relay

   The 'Pump driver relay' or 'Autoguidance relay' is likely located in a fuse and relay box either in the cab, possibly behind the operator's seat, or in the engine compartment. For T8010-T8050 models, a relay for the 'Tractor multi function (TMF)/autoguidance' is listed in the cab's relay identification chart.

2. 2

   Identify the Open Circuit

   Based on the diagnostic checks, determine the location of the open circuit. This could be a broken wire, a corroded pin in a connector, or an internal failure of the relay itself.

3. 3

   Repair or Replace Damaged Wiring

   If a break in the wiring is found, repair the damaged section using appropriate connectors and heat shrink to ensure a durable and weather-resistant connection.

4. 4

   Clean Connectors

   If corrosion is found on connector pins, clean them carefully.

5. 5

   Replace the Relay

   If the relay is determined to be faulty, replace it with a new, genuine OEM part.