Case IH 518350-02 - ACM – ACM: Transmission mode manual switch circuit fault

The control module is receiving an irregular or out-of-range electrical signal from the switch used by the operator to manually select the transmission mode.

• MAGNUM AFS Connect
• Magnum
• Steiger
• Puma
• Optum

1. 1

   Inspect the transmission mode manual switch on the armrest for physical damage, sticking, or liquid intrusion

2. 2

   Check the wiring harness connecting the switch to the ACM for pinched wires, chafing, or loose connector pins

3. 3

   Use a multimeter to test the switch's continuity across its different positions to verify if the internal contacts are failing

4. 4

   Verify that the ACM is communicating properly with the rest of the tractor's network via the CAN bus

1. 1

   Power down and disconnect battery

   Power down the machine and disconnect the battery to prevent electrical shorts.

2. 2

   Disassemble armrest console

   Carefully disassemble the armrest console housing to access the underside of the control panel.

3. 3

   Disconnect harness

   Disconnect the electrical harness from the transmission mode manual switch.

4. 4

   Repair wiring or remove switch

   If the wiring is damaged, repair the harness. If the switch failed the continuity test, unclip or unscrew the switch from the armrest bezel.

5. 5

   Install new switch

   Install the new switch and reconnect the harness.

6. 6

   Reassemble console

   Reassemble the armrest console.

7. 7

   Clear codes and test

   Reconnect the battery, power on the machine, and use a diagnostic tool to clear the pending/stored fault codes. Test the transmission mode selection to ensure the fault does not return.