Case IH 2707 – ZTC: PTCTL1 Message Missing/Timeout/Invalid (Intermediate Park Lock Switch)

The control module is unable to determine the physical position/status of the park lock mechanism because the signal from the intermediate park lock switch is not being broadcast correctly over the CAN bus.

• Steiger T4B
• Case IH Steiger AFS Connect series
• Case IH Magnum & Optum series (CVT models)

1. 1

   Check the fuses powering the ZTC module and the TCU (e.g., 5A switched power fuse).

2. 2

   Use the CNH Electronic Service Tool (EST) to monitor the CAN bus traffic for the PTCTL1 message.

3. 3

   Attempt to manually engage and disengage the park lock while monitoring the IPLS state in the diagnostic tool.

4. 4

   Inspect the wiring harness connecting the Intermediate Park Lock Switch to the transmission controller for chafed wires, moisture, or backed-out pins.

1. 1

   Secure the Machine

   Park the tractor on level ground. Because the park lock status is unverified, physically chock the wheels to prevent accidental rollaway.

2. 2

   Disconnect Power

   Turn off the battery isolator switch to de-energize the CAN network and prevent short circuits during testing.

3. 3

   Locate the Switch

   Locate the Intermediate Park Lock Switch, which is typically mounted on the side of the transmission housing near the park lock mechanical linkage or internal to the transmission valve block.

4. 4

   Test the Switch (Continuity)

   Disconnect the switch harness. Using a multimeter, test the switch for continuity. It should show a closed circuit in one position (engaged) and an open circuit in the other (disengaged).

5. 5

   Test the Harness (CAN/Signal Lines)

   If the switch tests good, use a multimeter to check the resistance of the CAN lines between the TCU and the ZTC module (should be ~60 ohms across CAN High and CAN Low). Check the signal wire from the switch to the TCU for continuity and short-to-ground.

6. 6

   Replace/Repair

   Replace the faulty Intermediate Park Lock Switch or repair the damaged section of the wiring harness.

7. 7

   Clear Codes and Calibrate

   Reconnect battery power. Use the CNH EST to clear the 2707 fault code. Cycle the park lock several times to ensure the ZTC module registers the PTCTL1 IPLS signal correctly.