Case IH 2464 - UCM – UCM / CCU: Shuttle lever R3 switch voltage too high

The control module is receiving a voltage signal from the switch circuit that exceeds the maximum valid operating range. This is almost always caused by a short circuit to a power source in the wiring harness or an internal failure/open circuit inside the shuttle lever switch itself.

• VESTRUM CVX
• Puma series (170, 185, 200, 215, 230 CVT)
• MXM series (e.g., MXM 190)
• Magnum series

1. 1

   Cycle the shuttle lever back and forth between Forward, Neutral, and Reverse multiple times to free up physically stuck micro-switches inside the lever assembly.

2. 2

   Ensure the lever isn't physically resting between detents, which can cause the module to read conflicting voltages.

3. 3

   Place the shuttle lever in NEUTRAL, access the switch connector under the steering column, and measure the voltage at the connector to see if a constant 12V or 5V is present where it shouldn't be (confirms a short to power in the wiring harness).

1. 1

   Prepare machine

   Park the tractor on a level surface, apply the parking brake, and turn the key off. Ensure the shuttle lever is in the NEUTRAL position.

2. 2

   Access shuttle lever base

   Remove the steering column covers and/or the instrument cluster to access the base of the shuttle lever. (Note: OEM manuals state that in some cases, you must remove the instrument cluster but keep it connected to properly test the CCU/UCM circuits).

3. 3

   Disconnect wiring

   Disconnect the main wiring connector at the shuttle lever switch.

4. 4

   Test switch continuity

   Using a multimeter, measure continuity across the switch pins (e.g., Pin A and B) while moving the lever into Forward and Reverse. If the switch does not show proper continuity when engaged, or shows continuity when it shouldn't, the switch has failed internally.

5. 5

   Inspect and repair wiring harness

   If the switch tests good, the fault lies in the tractor's wiring. Trace the harness from the steering column back to the UCM/CCU, looking for chafed wires shorting against the steering column frame or other powered wires. Repair any damaged wiring.

6. 6

   Replace faulty switch

   If the switch is faulty, unbolt the shuttle lever assembly from the steering column and install the replacement unit.

7. 7

   Reassemble and verify

   Reconnect the harness, reassemble the dash/steering column, and turn the key on to verify the active fault code has cleared.