New Holland DCU 19784 – DCU: Group error path NOx exceeded _Error belonging to group NOx exceeded active _P2000 Nox Trap Efficiency Below Threshold

The system has detected that the Selective Catalytic Reduction (SCR) system or NOx trap is not reducing nitrogen oxide emissions effectively enough to meet environmental standards. The measured NOx levels exiting the exhaust are too high, indicating that the efficiency of the emissions system has fallen below the required threshold.

• T6.125
• T6.145
• T6.155
• T6.165
• T6.175
• T6.180
• T7.165S
• T7.175
• T7.190
• T7.210
• T7.225
• T7.230
• T7.245
• T7.260
• T7.270
• T8.320
• T8.350
• T8.380
• T8.410
• T8.435
• T9.435
• T9.480
• T9.530
• T9.565
• T9.600
• T9.645
• T9.700

1. 1

   Scan for accompanying codes related to the NOx sensor (e.g., 3521, 3528, 3529, 3530) which indicate open loads, short circuits, or plausibility failures

2. 2

   Check DEF/AdBlue quality and level to ensure the tank is not empty and fluid is not degraded

3. 3

   Inspect the NOx sensor wiring harness and the 5-pin MCON connector for damage, corrosion, or short circuits

1. 1

   Cool down exhaust system

   Ensure the machine is turned off and the exhaust system has cooled down, as the NOx sensor is a high-temperature component located in the exhaust system.

2. 2

   Disconnect NOx sensor

   Locate the faulty NOx sensor and disconnect its electrical plug (5-pin connector).

3. 3

   Remove old sensor

   Unscrew and remove the old NOx sensor from the exhaust pipe.

4. 4

   Install new sensor

   Install the new replacement NOx sensor into the exhaust and tighten it securely.

5. 5

   Reconnect harness

   Reconnect the electrical harness.

6. 6

   Clear fault codes

   Connect a diagnostic scanner to the machine's OBD/diagnostic port and clear the DCU 19784 / P2000 fault code.