Case IH 2204 – ZDC: ZDC - Transmission CAN bus offline

Communication has been lost on the Controller Area Network (CAN) bus circuit responsible for transmission data. The ZDC can no longer share critical transmission data with the VCM/UCM, which will likely result in a loss of drive or restricted transmission functionality.

• Steiger T4B
• Steiger AFS Connect series
• Magnum CVT
• Puma CVX

1. 1

   Verify power to the ZDC by checking dedicated fuses F-101 (5 Amp) for switched power and 102 (7.5 Amp) for main power.

2. 2

   Inspect the CAN bus wiring harness between the ZDC, ZTC, and VCM/UCM for physical damage, chafing, or poor connector pin contact.

3. 3

   Test the CAN High and CAN Low lines for proper resistance (typically 60 ohms across the network when powered down) and check for shorts to ground or power.

1. 1

   Disconnect battery power

   Turn off the tractor and disconnect battery power before servicing the electrical system.

2. 2

   Check and replace ZDC fuses

   Locate the ZDC fuses (F-101 or 102) in the main fuse panel. If a fuse is blown, replace it. If the fuse blows again immediately upon key-on, trace the ZDC power circuit for a short to ground.

3. 3

   Inspect and clean harness contacts

   Disconnect the harness at the ZDC and the VCM/UCM. Clean the contacts with electrical contact cleaner and check for pushed-out pins.

4. 4

   Repair CAN bus wiring

   Repair any broken or shorted wires in the transmission CAN bus harness using OEM-approved wiring repair methods.

5. 5

   Replace and reprogram ZDC module

   If power, ground, and CAN bus wiring all test good, the ZDC module itself may have suffered an internal failure and will require replacement and reprogramming by a Case IH dealer.