New Holland NH 3021 – Engine Control Unit (ECU): Boost Pressure Signal - NO SIGNAL

The engine control system has lost communication with the boost pressure sensor. When the signal is lost, the system cannot dynamically tune the boost pressure to match engine speed and load, which typically results in reduced engine output or a default replacement value being applied by the system.

• T6.120
• T6.140
• T6.150
• T6.160
• T6.175
• T7.170
• T7.185
• T7.200
• T7.210
• T8.xxx
• TS110A
• TS125A
• TS135A
• T5 Series
• B110B
• B115
• LB110
• LB115
• SR130
• SR160
• SR175
• SV185

1. 1

   Check the boost pressure sensor (located on the intake manifold) and its electrical connector for physical damage, heavy soot blockage, or disconnected wires.

2. 2

   Test the wiring harness between the sensor and the Engine ECU for an open circuit, a short to ground, or a short to the power supply.

3. 3

   Verify that the CAN communication lines to the engine controller are intact and not suffering from voltage drops.

1. 1

   Disconnect battery

   Turn off the machine's ignition and disconnect the negative battery cable to prevent electrical shorts.

2. 2

   Locate sensor

   Locate the boost pressure sensor on the engine's intake manifold piping (usually near the turbocharger outlet or intake horn).

3. 3

   Unplug connector

   Depress the locking tab on the 4-pin electrical connector and carefully unplug it from the sensor.

4. 4

   Remove mounting bolt

   Remove the mounting bolt(s) securing the sensor to the manifold.

5. 5

   Remove and clean sensor port

   Pull the sensor straight out. Clean the mounting port on the manifold, ensuring no soot or debris falls into the intake.

6. 6

   Install new sensor

   Lubricate the O-ring on the new boost pressure sensor and press it firmly into the manifold port.

7. 7

   Tighten retaining bolt

   Install and tighten the retaining bolt to the manufacturer's specified torque.

8. 8

   Reconnect connector

   Reconnect the electrical connector until it clicks into place.

9. 9

   Clear code and test

   Reconnect the battery, turn the ignition on, and use a diagnostic scan tool to clear the NH 3021 fault code. Start the engine and verify that the code does not return.