Case IH 19082 (DTC 6C5A) - ECU – DCU (Dosing Control Unit) or Engine ECU (EDC17): DEF/AdBlue reverting valve driver circuit short to battery failure

The controller is detecting unexpected high voltage on the reverting valve circuit, likely due to a wiring short or an internal failure in the valve's electrical driver.

• MAXXUM T4E
• Case IH 240 Series Axial-Flow Combines (7240, 8240, 9240)
• Case IH Magnum Series 4 (235 - 340)
• Steiger
• Puma
• Maxxum
• Farmall CVT

1. 1

   Inspect the wiring harness and connectors leading to the urea fluid supply module for water intrusion, adhering foreign material, corrosion, or poor connections.

2. 2

   Use a multimeter to test the reverting valve power supply circuit (UB3) for an open circuit, high resistance, or a direct short to the battery.

3. 3

   Check for key-off voltage bleeding into the circuit when the ignition is switched off (Key 15 off).

4. 4

   Clear the DTC with a diagnostic scan tool and turn the ignition ON without starting the engine. If the code resets immediately, it indicates an internal hard failure of the supply module.

1. 1

   Preparation

   Turn OFF the ignition switch and wait for the system to fully power down and depressurize.

2. 2

   Disconnect Electricals

   Locate the DEF Supply Module (usually mounted near the DEF tank) and disconnect the main electrical connector.

3. 3

   Disconnect Fluid Lines

   Carefully disconnect the DEF/AdBlue supply and return lines, as well as the engine coolant lines attached to the module. Have a catch pan ready for minor coolant or DEF spillage.

4. 4

   Remove the Module

   Unbolt the DEF supply module from its mounting bracket and remove it from the machine.

5. 5

   Install the New Module

   Mount the replacement DEF supply module.

6. 6

   Reconnect Lines

   Reconnect the DEF/AdBlue lines and the coolant lines to the dosing module. Reconnect the electrical harness.

7. 7

   Clear Codes and Test

   Use a diagnostic scan tool to clear DTC 6C5A / 19082. Start the engine and allow the system to build pressure (normal operating pressure is around 9.0 bar / 130.5 psi) to ensure there are no leaks and the code does not return.