New Holland DCU 19145 – DCU: Dosing Valve (electrical) | short circuit to batt + | Reductant Injector - circuit high

This code indicates that the control unit has detected a high voltage condition (short circuit to battery positive) on the electrical circuit controlling the DEF (Diesel Exhaust Fluid) dosing valve, also known as the reductant injector.

• T6
• T7
• T8
• T9
• CX
• FR
• Magnum
• Steiger
• Puma
• Axial-Flow

1. 1

   Inspect the wiring harness connecting the DCU to the DEF dosing valve for chafed wires, melted insulation, or areas rubbing against the frame or exhaust.

2. 2

   Disconnect the plug at the DEF dosing valve and check for water ingress, corrosion, or bent pins that could bridge the power and control circuits.

3. 3

   Perform circuit isolation: with the dosing valve unplugged, turn the key on and check if the active fault code changes to DCU 18147 / P2047 (open load). If it changes, the short is internal to the valve. If it remains DCU 19145, the short is in the harness or DCU.

4. 4

   Test harness continuity using a multimeter to check the dosing valve control wire for continuity to battery voltage with the DCU and valve disconnected.

1. 1

   Replace DEF dosing module

   If the diagnostic checks isolate the short to the component, replace the DEF dosing module (injector).

2. 2

   Repair or replace wiring harness

   If the wiring harness is damaged and shorting to power, repair the broken/chafed section of the harness or replace the harness entirely.

3. 3

   Replace UREA pump module

   If the error is still present after replacing the dosing valve and verifying the wiring, the internal circuitry of the UREA pump module or DCU may be compromised, requiring pump module replacement.

4. 4

   Clear codes and test

   After repairs, clear the fault codes and run an SCR system test or perform a forced regeneration to verify the dosing valve is operating correctly without throwing a high-circuit code.