CLAAS Id78A5h / 78A5h – EXT (A62) module: CSM Switch (S177) Not in Play Position

The system logs this code when the operator attempts to select or initiate a saved headland management sequence, but the CSM switch (S177) is not in the correct position.

• CLAAS Arion 640 - 510
• CLAAS Axion 850 - 810
• CLAAS Axion 950 - 920

1. 1

   Verify the physical position of the CSM (S177) switch on the control panel

2. 2

   Test the S177 switch for proper electrical continuity if it is already in the 'Play' position

3. 3

   Check the wiring harness between the S177 switch and the EXT (A62) module

4. 4

   Verify that the EXT module is communicating properly on the CLAAS vehicle CAN bus network

1. 1

   Correct Switch Position

   Locate the CSM (CLAAS Sequence Management) switch (S177) in the cab. Move the switch to the 'Play' position.

2. 2

   Test Operation

   Attempt to select the sequence again. If the sequence activates and the code clears, no further repair is needed—it was simply an operator sequence error.

3. 3

   Test the Switch

   If moving the switch to 'Play' does not resolve the issue, use a multimeter to test the S177 switch. If the switch fails to close the circuit when toggled to 'Play', remove and replace the switch.

4. 4

   Inspect Wiring

   Trace the wiring from the S177 switch to the EXT (A62) module. Look for chafed wires, loose connector pins, or corrosion. Repair as necessary.

5. 5

   Module Verification

   If the switch and wiring are intact, the EXT (A62) module may be failing to process the input, requiring a module reset or replacement by a CLAAS dealer.