Case IH 17673 (F-3362-07) - ECU – Engine ECU: SCR dosing valve leakage detected when dosing is not active

Mechanical or hydraulic failure within the Diesel Exhaust Fluid (DEF / AdBlue) dosing valve (doser injector). The system has detected that the valve is stuck open or leaking DEF fluid into the exhaust stream during a period when the emissions system is not actively commanding an injection.

• VESTRUM CVX
• Magnum Series (180, 200, 220, 240, 250, 280, 310, 340, 380)
• Puma Series (140, 150, 165, 185, 200, 220, 240)
• Maxxum Series (115, 125, 135, 145, 150)
• Optum Series (270, 300)
• Farmall Series (115U)
• Axial-Flow Combines (7230)

1. 1

   Perform a Dynamic Leakage Test or Dosing Quantity Test using a diagnostic scan tool to pressurize the system and monitor for pressure drops confirming the leak.

2. 2

   Visually inspect the DEF dosing valve nozzle at the exhaust pipe for heavy, white DEF crystallization buildup around the nozzle and exhaust mounting boss.

3. 3

   Check DEF fluid quality and inspect the DEF filter for contamination or debris, which is a primary cause of the dosing valve pintle sticking open.

1. 1

   Cool Down

   Turn off the machine and allow the exhaust system to cool completely. The dosing valve is mounted directly to the hot exhaust/SCR catalyst pipe.

2. 2

   Disconnect Electrical

   Unplug the electrical wiring harness connector from the DEF dosing valve.

3. 3

   Disconnect Fluid Line

   Disconnect the DEF supply line from the valve. Note: Have a rag ready to catch residual DEF fluid. DEF is highly corrosive to metals and wiring; clean up any spills immediately with warm water.

4. 4

   Remove the Valve

   Remove the mounting bolts or V-band clamp securing the dosing valve to the exhaust pipe boss. Pull the valve free.

5. 5

   Clean the Boss

   Thoroughly clean the mounting boss on the exhaust pipe. Scrape away any crystallized DEF or carbon buildup to ensure the new valve seats perfectly.

6. 6

   Install New Valve

   Install the new DEF dosing valve using a new OEM mounting gasket/seal.

7. 7

   Reassemble

   Secure the mounting bolts/clamp and torque to OEM specifications. Reconnect the DEF supply line and the electrical harness.

8. 8

   Filter Replacement

   Replace the main DEF filter (and inline screens if applicable) to prevent old debris from ruining the new injector.

9. 9

   Clear and Test

   Use your diagnostic tool to clear the 17673 fault code. Run a system prime/leak test to ensure the new valve holds pressure and there are no external leaks.