Case IH 2203 – ZDC: ZDC - CAN broadcast inhibited on transmission bus due to DM13 reception

Normal communication on the transmission CAN bus has been intentionally or erroneously suspended due to receiving a DM13 (Stop/Start Broadcast) command.

• Steiger T4B
• Case IH tractors equipped with a CVT
• Steiger AFS Connect series

1. 1

   Check for Connected Service Tools: Verify if a diagnostic scan tool (like the CNH Electronic Service Tool) is currently or was recently plugged into the diagnostic port.

2. 2

   Cycle the Key: Turn the tractor off, wait for the modules to power down completely, and restart to see if the code clears.

3. 3

   Check for Rogue Modules: If no tool is connected and the code persists after a power cycle, check if another module on the transmission CAN bus is malfunctioning and erroneously broadcasting the DM13 stop command.

1. 1

   Disconnect devices

   Disconnect any aftermarket CAN devices, telematics units, or diagnostic scan tools from the tractor's diagnostic port.

2. 2

   Power down modules

   Turn the ignition key to the OFF position and allow the ZDC and other modules to fully power down (wait at least 2-3 minutes).

3. 3

   Turn ignition ON

   Turn the ignition key back to the ON position.

4. 4

   Check fault code status

   Use a diagnostic tool to check if the 2203 fault code has moved from "Active" to "Inactive/Previously Active" (DM2).

5. 5

   Monitor transmission bus

   If the code remains active, use a CAN bus analyzer or oscilloscope to monitor the transmission bus for rogue DM13 messages (PGN 57088 / 0x00DF00).

6. 6

   Isolate modules

   Isolate modules on the transmission bus one by one to determine which ECU is improperly broadcasting the DM13 command.