Case IH 18320 (4159.02, 4159.03, 4159.04, 520606.07) - ACML – ACML: Rear Hitch Lower Switch Error State

The system has detected a malfunction—such as an invalid signal, open circuit, or short—originating from the switch used by the operator to command the rear hitch to lower.

• MAXXUM T4E
• VESTRUM CVX
• Puma 150
• Puma 190
• Puma 200
• Puma 205
• Puma 215
• Puma 225
• Puma 230
• Maxxum 115
• Maxxum 125
• Maxxum 135
• Maxxum 150
• Vestrum 130

1. 1

   Connect the Case IH Electronic Service Tool (EST) to monitor the live data state of parameter 'Config B/b 3.7' (Rear hitch lower switch).

2. 2

   Check if the switch is stuck, unresponsive, or sending an out-of-range voltage.

1. 1

   Isolate the failure point

   Isolate whether the failure is in the physical switch on the armrest, the wiring harness connecting the switch to the ACML, or the ACML itself.

2. 2

   Replace and reprogram the ACML

   If the switch and wiring are intact but the EST still shows an error state, the ACML may require replacement and reprogramming.