New Holland NH 14903 – CAN Network / Main Controller: SCM controller missing (GA 12x12 only)

CAN Network communication error indicating that the Small Control Module (SCM) has dropped offline and is no longer communicating with the rest of the tractor's network.

• T6010
• T6020
• T6030
• T6040
• T6050
• T6060
• T6070
• TL90a

1. 1

   Check cab mini fuses powering the SCM (e.g., Fuse 36, Fuse 38, and Fuse 16 on T6000 series)

2. 2

   Inspect CAN bus wiring (yellow and green wires) for continuity, open circuits, or shorts to ground

3. 3

   Inspect main wiring harnesses leading to the transmission and SCM for damaged, chafed, or half-severed wiring

1. 1

   Verify error code

   Verify the active error code (NH 14903) on the Analogue Digital Instrument Cluster (ADIC).

2. 2

   Locate module

   Locate the SCM (Small Control Module) / GA Module on the tractor.

3. 3

   Test power and ground

   Using a multimeter, test the power and ground circuits at the SCM connector to ensure the module is receiving adequate voltage.

4. 4

   Test CAN bus wiring

   Test the CAN bus wiring (yellow and green wires) between the SCM and the diagnostic connector/main network for continuity.

5. 5

   Repair wiring or replace fuses

   Repair any damaged wiring or replace blown fuses discovered during the diagnostic checks.

6. 6

   Replace SCM

   If power, ground, and CAN lines are all intact and functioning properly but the module still fails to communicate, the SCM itself has failed internally and must be replaced.

7. 7

   Install and test

   Install the new SCM, clear the fault codes, and test the tractor to ensure the transmission and network operate correctly without triggering the warning lamp.