Case IH 41 – Transmission Control Unit (TCU) / Rear Linkage Control Unit (TC1) / Armrest / Cab Controller: Clutch Pack A PWM Solenoid Fault / Ground Speed Radar Signal Absent / Auto PTO Indicator Short

Depending on the active module, this code indicates the Clutch Pack A (Lo-Forward) PWM solenoid has a short to ground, open circuit, or open ECM drive; the ground speed radar signal is absent; or the Auto PTO indicator lamp circuit has shorted.

• MX Maxxum
• Case IH Magnum and MX Series (MX180-MX285)
• Case IH Puma and Maxxum Series
• Case IH Steiger / STX Series

1. 1

   Identify the active module (transmission status lamp, hitch controller, or guidance display) to isolate the correct system.

2. 2

   For Transmission Code 41: Check the wiring harness between the TCU and the Clutch Pack A PWM solenoid for continuity (open circuit) or a short to ground.

3. 3

   For Transmission Code 41: Test the resistance of the PWM solenoid itself to ensure it is not internally shorted.

4. 4

   For Linkage Code 41: Inspect the B10 Ground Speed Radar connector for dirt, corrosion, or moisture.

5. 5

   For Linkage Code 41: Verify the radar wiring harness for continuity back to the TC1 controller (Input Fi7).

6. 6

   For the Auto PTO Indicator Lamp: Trace the specific circuit (e.g., Pin 16 on the cab controller harness) to the instrument cluster and check for pinched wires under the right-hand console or armrest.

1. 1

   Park tractor

   If repairing the Transmission PWM Solenoid (Code 41): Park the tractor on a level surface, turn off the engine, and engage the parking brake.

2. 2

   Locate valve block

   Locate the transmission control valve block on the side of the transmission housing.

3. 3

   Disconnect harness

   Disconnect the wiring harness from the Clutch Pack A (Lo-Forward) PWM solenoid.

4. 4

   Repair wiring

   If the harness is damaged or shorted to the chassis, repair the wiring using OEM-approved splice kits and heat shrink.

5. 5

   Extract solenoid

   If the solenoid tests out of specification (internal short), remove the retaining bolt and extract the solenoid from the valve block.

6. 6

   Install new solenoid

   Lubricate the O-rings on the new solenoid with clean hydraulic oil and install it into the valve block.

7. 7

   Reconnect and clear codes

   Reconnect the harness, clear the fault codes via the diagnostic menu, and cycle the Power Shuttle FNR to re-enable the transmission.

8. 8

   Disconnect battery

   If repairing the Auto PTO Indicator Circuit: Disconnect the battery to prevent further electrical damage.

9. 9

   Remove trim panels

   Remove the interior trim panels to access the armrest controller and the instrument cluster wiring.

10. 10

    Locate short

    Locate the wire responsible for the Auto PTO indicator. Use a multimeter to find the exact point of the short to ground.

11. 11

    Repair wire

    Repair the chafed wire, wrap it in protective loom, and secure it away from pinch points.

12. 12

    Replace bulb

    Replace the indicator bulb or LED in the dash if it was blown by the short.