New Holland ENG 3363 – Engine Control Unit (ECU): Atmospheric Pressure Sensor - Processed via ADC (no CAN Plausibility Performed)

The Engine Control Unit (ECU) is receiving an implausible or unreadable signal from the atmospheric (barometric) pressure sensor through its internal Analog-to-Digital Converter (ADC).

• New Holland T8.xxx Series
• New Holland B110
• New Holland B110B
• New Holland LB110
• New Holland B115
• New Holland LB115
• Case 580N
• Case 590
• Case 695
• New Holland CR9090
• New Holland CX8080 Elevation
• New Holland CX8090 Elevation

1. 1

   Check ECU venting to ensure the housing is clean and the small breather vent is not packed with mud, grease, or debris.

2. 2

   Verify sensor plausibility using the CNH Electronic Service Tool (EST). With the engine OFF (key ON), compare the Atmospheric Pressure Sensor reading to the Boost Pressure Sensor reading; they should be nearly identical.

3. 3

   Inspect the main engine wiring harness connectors at the ECU for corrosion, bent pins, or moisture intrusion.

4. 4

   Verify battery voltage and ensure chassis grounds are clean and tight to rule out voltage spikes or poor grounding.

1. 1

   Disconnect battery

   Turn off the machine and disconnect the negative battery cable to prevent electrical arcing.

2. 2

   Locate the Engine ECU

   Typically mounted directly to the side of the engine block on FPT engines.

3. 3

   Disconnect ECU wiring harnesses

   Carefully release the locking levers on the main wiring harness connectors and unplug them from the ECU.

4. 4

   Remove the ECU

   Remove the mounting bolts securing the ECU to the engine block (often mounted on rubber isolation dampeners).

5. 5

   Install replacement ECU

   Install the replacement Engine ECU and tighten the mounting bolts.

6. 6

   Reconnect wiring harnesses

   Reconnect the wiring harnesses, ensuring the locking levers click fully into place.

7. 7

   Reconnect battery

   Reconnect the negative battery cable.

8. 8

   Program the new ECU

   Connect the CNH EST diagnostic laptop to flash the ECU with the correct software, engine calibration files, and injector trim codes specific to your machine's serial number.