Case IH 517962-16 - DEC – DEC: Transmission low clutch solenoid electrical circuit fault voltage high

The system has detected that the valid data from the low clutch solenoid circuit is above the normal range (most severe). This typically means the low clutch solenoid circuit is shorted to a +12 Volt power source, and current is being sensed even when the driver/controller is commanding it to be off.

• MAGNUM AFS Connect
• Case IH Magnum AFS Connect Series
• Case IH Magnum Series 4 (235 - 340)
• Case IH Steiger Series

1. 1

   Harness Inspection: Inspect the wiring harness running from the DEC to the transmission control valve manifold. Look for chafed wires that may be shorting to a +12V power wire.

2. 2

   Connector Check: Disconnect the plug at the Low Clutch Solenoid. Inspect for water ingress, corrosion, or melted/pushed pins that could bridge the power circuit.

3. 3

   Solenoid Resistance Test: Test the resistance across the pins of the Low Clutch Solenoid coil. The OEM specification for this Pulse-Width Modulation (PWM) solenoid (14-Watt) is approximately 9.9 Ohms. If the resistance is significantly lower or reads as a dead short, the solenoid coil has failed internally.

4. 4

   Voltage Check: With the key ON and the solenoid disconnected, probe the harness side. If +12V is constantly present on the control wire when the clutch is not being commanded, the harness is shorted to power or the DEC has an internal fault.

1. 1

   Power Down

   Turn off the tractor, remove the key, and disconnect the battery to prevent electrical spikes.

2. 2

   Locate the Valve Manifold

   Access the transmission powershift valve manifold, which is typically mounted on top of the range transmission.

3. 3

   Identify the Solenoid

   Locate the Low Clutch Solenoid. It is usually grouped in a block alongside the MFD, Mid Clutch, and High Clutch solenoids.

4. 4

   Remove the Solenoid

   Disconnect the electrical connector. Remove the retaining nut at the top of the solenoid coil and slide the coil off the valve cartridge stem. (If the cartridge valve itself is damaged, unscrew the entire cartridge from the manifold).

5. 5

   Install the New Part

   Slide the new PWM solenoid coil onto the cartridge stem and secure it with the retaining nut. If replacing the whole cartridge, ensure the new O-rings (e.g., 0.07" O-rings) are lubricated with clean transmission fluid before threading it into the manifold.

6. 6

   Reassemble

   Reconnect the electrical plug securely.

7. 7

   Calibrate

   Reconnect the battery. Clear the inactive fault codes from the DEC using the AFS Pro monitor or a diagnostic tool. You will likely need to perform a transmission clutch calibration procedure so the DEC can learn the fill times and engagement profile of the new solenoid.