Case IH t87 – Pump Control Unit (PCU) / Engine Control Unit (ECU) or Transmission Controller: Solenoid Valve Power Stage, Data Valid But Above Normal Range

The control module is receiving a valid signal from the solenoid valve's power stage, but the electrical value (typically voltage or resistance) is higher than the expected normal operating parameters. This usually points to high resistance in the circuit, a failing solenoid coil, or a wiring harness issue.

• MXM
• MXM 120
• MXM 130
• MXM 140
• MXM 155
• MXM 175
• MXM 190

1. 1

   Turn the Power OFF and Keyswitch OFF, and disconnect the battery or specified fuse

2. 2

   Disconnect the connectors at each end of the solenoid circuit to isolate the circuit and prevent false readings

3. 3

   Set a multimeter to measure resistance (ohms)

4. 4

   Perform a ground check by connecting a multimeter's black lead to a clean, plated metal part on the chassis

5. 5

   Perform pin testing by using the red meter lead to touch the connector pins one at a time, avoiding the metal case

6. 6

   Measure the circuit resistance (ohms) and evaluate if it falls within the normal range

7. 7

   If resistance is above normal, inspect the wiring harness for corrosion, partial open circuits, or loose pins; if the wiring is intact, the solenoid itself is likely faulty

1. 1

   Wiring Repair

   If the diagnostic checks reveal damaged wiring or corroded connector pins leading to the solenoid valve, repair or replace the affected harness section.

2. 2

   Solenoid Replacement

   If the wiring is good but the solenoid fails the resistance test, remove and replace the faulty PWM (Pulse Width Modulation) transmission/EDC solenoid valve.

3. 3

   Mandatory Calibration

   If a PWM solenoid valve has been replaced, a Transmission/EDC Calibration Set Up Procedure is required.

4. 4

   Calibration Setup

   Ensure the transmission fluid temperature is between 20°C and 50°C. Apply the parking brake. Turn off the air conditioning (if fitted) and deselect all electrical and hydraulic services. For EDC systems: Turn all EDC controls fully clockwise and position the raise/work switch to the WORK position.

5. 5

   Execute Calibration

   Enter calibration mode (typically by holding the High and Low range buttons while starting the engine until 'CAL' appears on the transmission display). Set the engine speed to 1200 RPM (±100) and follow the on-screen prompts to complete the clutch/solenoid calibration until 'END' is displayed.