Case IH 19771 – CDM (Chemical Dosing Module): Deviation from the dosing quantity detected during Test Injection

During a routine self-test or 'Test Injection' cycle, the system detected that the actual amount of urea (AdBlue/DEF) being injected by the dosing valve deviated from the expected or commanded quantity.

• Tier 4b
• Case IH tractors and combines equipped with Tier 4B / Stage IV or newer engines

1. 1

   Check the DEF/urea dosing valve (injector) at the exhaust for severe crystallization or physical blockage

2. 2

   Inspect the DEF supply lines between the pump and the dosing module for kinks, leaks, or blockages

3. 3

   Use an electronic diagnostic tool to manually trigger a DEF dosing quantity test to measure the actual output volume against the expected parameter

1. 1

   Clean dosing valve

   Clean the dosing valve of crystallized urea.

2. 2

   Replace dosing valve

   Replace the dosing valve entirely if it fails the manual quantity test.