Case IH U34 – Transmission Control Module / Electronic Draft Control (EDC) / Chassis Control Module (CCM): C2 calibration value is too low

Indicates that the C2 calibration value is too low. This is triggered during a transmission/clutch calibration if the engine RPM dropped too soon, the clutch pressure is not being controlled properly, the engine speed was adjusted whilst completing the calibration, or a mechanical failure has occurred, breaking the torque path.

• Maxxum
• Farmall 40
• Farmall 45
• Farmall 50 CVT
• Farmall 55C
• Farmall 65C
• Farmall 115U
• Maxxum MXM 120
• Maxxum MXM 130
• Maxxum MXM 140
• Maxxum MXM 155
• Maxxum MXM 175
• Maxxum MXM 190
• Maxxum MXU 125
• Maxxum MXU 130
• Puma 140
• Puma 180-260 CVX
• Puma 195
• Puma 210
• CX Series

1. 1

   Check transmission oil temperature to ensure it is between 20°C and 100°C (look for 'CL' or 'CH' warnings on the display)

2. 2

   Verify operator error: ensure engine speed is kept completely steady and not manually adjusted during the calibration procedure

3. 3

   Perform a hydraulic pressure test on the C2 PWM Solenoid Valve to verify if clutch pressure is being controlled properly (pressure should rise and fall between 0 to 18 bar)

1. 1

   Warm Up the Tractor

   Bring the transmission oil temperature to the required range (20°C – 100°C).

2. 2

   Enter Calibration Mode

   Method 1 (Using Diagnostic Tool): Connect the Case IH special diagnostic bypass tool to the diagnostic connector and enter the 'H1' menu mode. Method 2 (Manual Procedure): Sit in the operator seat and hold down the clutch pedal. With the key switch OFF, depress and hold the upshift switch. Start the engine, and within 2 seconds, depress and release the downshift switch. Release the clutch to begin.

3. 3

   Run Calibration

   Allow the tractor to calibrate the C2 clutch. Do not adjust the engine RPM during this process.

4. 4

   Inspect the Valve Block

   If the calibration fails again and logs U34, the C2 PWM solenoid valve is likely failing to control pressure. Locate the transmission control valve assembly.

5. 5

   Replace the C2 PWM Solenoid Valve

   Remove the faulty C2 PWM solenoid valve. Coat the new valve components and O-rings with clean transmission oil (CASE IH AKCELA NEXPLORE FLUID) prior to assembly.

6. 6

   Torque Specifications

   Install the new valve and tighten the retaining bolts to a torque value of 27 Nm.

7. 7

   Recalibrate

   Re-run the electronic clutch calibration procedure to verify the repair.