New Holland DCU 19110 – DCU (Dosing Control Unit): UREA Temperature sensor in Tank (electrical) | signal low

The voltage signal coming from the Diesel Exhaust Fluid (DEF / Urea) tank temperature sensor has dropped below the minimum acceptable limit. This condition is typically caused by a short circuit to ground in the wiring or a total internal failure of the sensor itself.

• T6
• T7
• T7.220
• T7.235
• T7.250
• T7.260
• T7.270
• T8
• T9
• SP280
• SP480
• W190B

1. 1

   Stop the engine and let it cool completely before starting work. Do not start the engine during the service procedures.

2. 2

   Check the wiring harness and connector at the DEF tank head unit for physical damage.

3. 3

   Inspect the connector pins for debris or water ingress inside the terminals, which is a very common consequence of aggressive pressure washing.

4. 4

   Check for any damaged or loose machine earths (grounds).

5. 5

   Test the wiring harness between the DEF tank temperature sensor and the DCU to rule out a short circuit to ground in the chassis wiring.

1. 1

   Cool down machine

   Turn off the machine and allow the exhaust and aftertreatment systems to cool.

2. 2

   Disconnect harness

   Disconnect the electrical harness at the DEF tank sending unit.

3. 3

   Clean and test connector

   Clean and dry the connector terminals. If water or debris was bridging the connections and causing the short, reconnect and check if the fault code clears.

4. 4

   Diagnose internal sensor failure

   If the wiring harness tests good and the connector is clean, the fault is internal to the DEF tank temperature sensor. The temperature sensor is not serviced separately; it is integrated into the DEF Head Unit.

5. 5

   Remove faulty assembly

   Remove the mounting hardware securing the DEF Head Unit to the DEF tank and extract the faulty assembly.

6. 6

   Install replacement and clear codes

   Install the replacement DEF Head Unit, reconnect the electrical harness, and use a diagnostic tool to clear the DCU 19110 / P205C fault codes.