New Holland ENG 3346 – Engine Controller (EDC - Electronic Diesel Control): Multiple State Switch

A malfunction or implausible signal coming from the multiple state switch, which is an input used by the engine controller to select different operating states, such as fixed engine speeds (e.g., cruise control or PTO speed presets) or specific torque curves.

• T8.xxx Series
• Puma CVX (165, 180, 195)
• CR9090
• CX8080 Elevation
• CX8090 Elevation (Tier 4A)
• Magnum 235 - 340 (Series 4)

1. 1

   Scan the system using the CNH EASy tool to retrieve active DTCs and verify if related codes (3347, 3348, 3349) are present

2. 2

   Inspect cab controls (multi-function handle, hand throttle, or PTO preset switches) for physical damage or sticking buttons

3. 3

   Inspect the wiring harness between the cab's Multiple State Switch (Pass Input #06) and the Engine ECU for chafed wires, loose pins, or corrosion

4. 4

   Monitor live data using a diagnostic tool while toggling the cab controls to verify if the ECU registers the state changes

1. 1

   Isolate the Circuit

   Disconnect the battery to ensure safety. Disconnect the harness at the Multiple State Switch and at the Engine ECU.

2. 2

   Test Continuity

   Using a multimeter, test the continuity of the signal wires from the switch connector to the ECU connector. Repair any breaks in the wiring harness.

3. 3

   Test the Switch

   Test the Multiple State Switch itself for proper resistance/continuity across its different states. If the switch fails to change states or shows an open/short internally, it must be replaced.

4. 4

   Reassemble and Clear Codes

   Reconnect all harnesses. Reconnect the battery. Use the CNH EASy tool or a compatible CAN-Bus DTC eraser to clear the fault codes from the Engine ECU.

5. 5

   Operational Test

   Start the machine and cycle through the engine speed presets/throttle states to ensure the code does not return.