Case IH 19265 – DCU: Tank heating Valve - short circuit to ground

The electrical circuit controlling the Diesel Exhaust Fluid (DEF) / Reagent tank heating valve has experienced a short to ground or a low voltage condition.

• Tier 4a
• Case IH Steiger tractors (350 to 600 horsepower)
• Case IH Magnum 235 - 340 (Series 4)
• Case IH Puma series
• Case IH F-Series Loaders (721F, 821F, 921F)

1. 1

   Inspect the DEF tank heating valve to ensure it is operating normally and is not physically stuck open

2. 2

   Verify that the DEF heater lines are connected correctly (e.g., on Fargo-built tractors, the DEF heater line with the 'red' band must be connected to the top tube running to the front part of the engine head)

3. 3

   Inspect the wiring harness between the DCU and the tank heating valve for rubbed-through insulation, pinched wires, or moisture in the connectors causing a short to the chassis

1. 1

   Correct wiring shorts

   Correct any wiring shorts found between the DCU and the heating valve.

2. 2

   Reroute DEF tank hoses

   If the DEF tank hoses were installed incorrectly, reroute them to their proper configuration.

3. 3

   Replace heater control valve

   If the heating valve is found to be stuck open, damaged from overheating, or if the fault returns repeatedly after clearing, replace the heater control valve.

4. 4

   Erase fault code and verify

   Once the repair or replacement is complete, erase the fault code from the DCU and operate the machine to verify the code does not return.