Case IH P88 – Transmission Controller or Electronic Draft Control (EDC) module: Solenoid Valve Power Stage 2, Data Valid But Below Normal Range

The control module has detected that the electrical signal (voltage or current) feeding the power stage 2 of a transmission or hydraulic solenoid valve has dropped below the acceptable operating threshold. This typically points to a failing solenoid coil, a wiring issue, or a failing output driver within the controller itself.

• MXM
• MXM 120
• MXM 130
• MXM 140
• MXM 155
• MXM 175
• MXM 190
• MXU
• Puma
• Maxxum

1. 1

   Visual Inspection: Inspect the wiring harness running from the transmission controller to the transmission solenoid valve block for chafed wires, pinched harnesses, or corroded connector pins.

2. 2

   Voltage & Resistance Testing: Disconnect the affected solenoid valve and measure its internal resistance using a multimeter to compare to OEM specifications. Check the supply voltage at the connector to ensure the controller is sending the correct voltage (typically 12V).

3. 3

   Controller Output Check: If the wiring and solenoid test fine, check the controller's output stage (Error Code 42 is often related to an internal pilot solenoid valve fault).

1. 1

   Isolate the Fault

   Based on your multimeter tests, determine if the fault is the wiring harness or the solenoid itself.

2. 2

   Replace the Solenoid

   If the solenoid coil is degraded (causing the 'below normal range' reading), safely relieve any hydraulic pressure, disconnect the electrical connector, unbolt the faulty solenoid valve from the transmission valve block, and install the replacement.

3. 3

   Perform a Transmission Calibration

   Ensure the transmission oil temperature is between 20°C and 50°C. Apply the parking brake. Turn off the air conditioning and deselect all electrical and hydraulic services. Press and hold the High and Low range buttons, then start the engine. Release the buttons when 'CAL' appears on the transmission display. Set the engine speed to 1200 RPM (± 100 RPM). Follow the on-screen prompts to complete the clutch and synchronizer calibration.