Case IH 3359-06 - VCM – VCM: Transmission filter restriction switch, clean switch terminal

Indicates a circuit anomaly related to the Transmission Filter Restriction Switch. The controller is detecting abnormal resistance (likely an open circuit or high resistance) caused by dirt, debris, or corrosion at the electrical connection rather than an actual filter blockage.

• MAGNUM AFS Connect
• Magnum series
• MX210
• Magnum 310
• Steiger series
• 9300 series
• 9370
• 9380
• 9390
• 521D
• 621D
• 621E
• 821E
• 921C
• 921F
• W190B

1. 1

   Visually inspect the transmission filter housing and restriction switch connector for heavy dirt accumulation, moisture, or green corrosion on the pins.

2. 2

   Disconnect the switch and measure resistance across the terminals with a multimeter (should read exactly 510 ohms; infinite resistance/OL indicates internal failure).

3. 3

   Check the wiring harness leading back to the VCM for chafing, broken wires, or short circuits.

4. 4

   Verify if the transmission filter restriction warning lamp is illuminated on the dash, which may indicate a genuine filter restriction.

1. 1

   Clean the Terminal (Primary Fix)

   Disconnect the 2-pin electrical connector from the transmission filter restriction switch. Use a dedicated electrical contact cleaner and a soft terminal brush to thoroughly clean both the male pins on the switch and the female sockets on the harness connector.

2. 2

   Apply Dielectric Grease

   Once dry, apply a small amount of dielectric grease to the connector to seal out moisture and dirt, preventing future high-resistance faults.

3. 3

   Reconnect and Clear Codes

   Reconnect the harness, turn the key on, and use the diagnostic menu or a service tool to clear the VCM fault codes.

4. 4

   Replace Switch (If Necessary)

   If the switch failed the 510-ohm resistance test during diagnostics, unthread the old switch from the filter housing, install the new switch, and torque to OEM specifications.

5. 5

   Replace Filter (If Necessary)

   If the restriction warning lamp remains on after the circuit is repaired, the transmission filter is clogged. Drain the housing, remove the old filter, and install a new OEM Case IH transmission filter.