New Holland ENG 3349 – ENGINE: Multiple State Switch

The Engine Control Unit (ECU) has detected an implausible signal, circuit error, or communication timeout related to a 'Multiple State Switch.' This is often due to an open/short circuit on the ECU input (PASS.INPUT#06) or a CAN bus message timeout (TSC1 Receive Timeout-Error).

• New Holland T8.xxx Series tractors
• New Holland CR/CX Series Combines and Telehandlers

1. 1

   Connect the CNH Electronic Service Tool (EST) or FPT EASY diagnostic tool to confirm if ENG 3349 is active or stored.

2. 2

   Monitor the live data of the cab switches (specifically the fixed engine speed selectors, hand throttle, or multi-function handle switches) using the diagnostic tool. Cycle the switches to see if the ECU recognizes the changes.

3. 3

   Visually inspect the wiring harness between the armrest/console switches and the Engine ECU. Look for chafed wires, pinched harnesses, or corroded connector pins.

4. 4

   Verify that the armrest controller is communicating properly with the Engine ECU over the CAN bus to rule out a TSC1 (Torque/Speed Control) CAN timeout.

1. 1

   Power Down

   Turn off the machine, remove the key, and turn the battery disconnect switch to the OFF position to prevent electrical shorts during testing.

2. 2

   Access the Switch

   Remove the trim panels on the armrest or side console to access the back of the suspected multiple state switch (e.g., the fixed engine speed selector).

3. 3

   Test the Switch

   Disconnect the switch harness. Using a digital multimeter, test the continuity and resistance of the switch across all of its physical positions. If the switch shows an open circuit internally where there should be continuity, the switch has failed mechanically/electrically.

4. 4

   Test the Harness

   If the switch tests good, perform a continuity and short-to-ground test on the wiring harness from the switch connector back to the Engine ECU (specifically checking the circuit for PASS.INPUT#06 and the CAN High/Low lines).

5. 5

   Repair/Replace

   Repair any broken or shorted wires in the harness. If the switch itself failed the multimeter test, replace the switch assembly.

6. 6

   Reassemble and Clear Codes

   Reconnect all harnesses, reassemble the console, and turn the battery disconnect back on. Use the CNH EST tool to clear the ENG 3349 fault code.

7. 7

   Operational Test

   Start the engine and operate the multiple state switch through all its positions to ensure the engine responds correctly and the fault code does not return.