Case IH 2689 – ZTC: CAN Message EHR Timeout

Fault code 2689 indicates that the Zone Tractor Controller (ZTC) has lost Controller Area Network (CAN) bus communication with the Electro-Hydraulic Remote (EHR) module. The ZTC is not receiving the expected data packets from the EHR module within the programmed time limit, which can cause the hydraulic remotes to lock up.

• Steiger T4B
• Case IH Steiger series
• Case IH Quadtrac series
• Case IH Magnum series
• Case IH Optum series
• Case IH Puma LWB series
• Case IH CVX series

1. 1

   Check the fuses powering the ZTC and EHR modules (e.g., the 7.5A fuse for the ZTC controller on Steiger models).

2. 2

   Inspect the EHR control valve wiring harness for physical damage, chafing, or pinched wires.

3. 3

   Check the CAN bus connectors at the EHR pilot heads for corrosion, moisture ingress, or backed-out pins.

4. 4

   Determine if the fault occurs only when a specific remote (e.g., SCV 1 or SCV 4) is actuated to isolate the failure to a single EHR pilot head.

1. 1

   Power down machine

   Turn off the tractor, engage the parking brake, and disconnect the battery to prevent electrical spikes.

2. 2

   Access the EHR valves

   Locate the remote control valves at the rear of the tractor. The EHR modules (pilot heads) are mounted directly to these valves.

3. 3

   Test the CAN circuit

   Using a multimeter, test the CAN High and CAN Low lines between the ZTC and the EHR module for continuity, shorts to ground, or shorts to power.

4. 4

   Replace the faulty component

   If the wiring harness is intact and power and ground are verified, the communication failure is likely internal to the EHR module. Remove the retaining hardware and replace the faulty EHR module.

5. 5

   Reassemble and clear codes

   Reconnect the battery, turn the key on, and use a diagnostic tool (such as the CNH EST or Jaltest) to clear the stored 2689 fault code from the ZTC memory. Test the hydraulic remotes to ensure the system no longer locks up.