Case IH 19773 – Engine Control Module (ECM) or Dosing Control Unit (DCU): Maximum number restarts allowed by restriction counter is exceeded

This is an SCR (Selective Catalytic Reduction) software inducement code. It means the engine has been locked out from restarting because a severe emissions system fault (such as an empty DEF tank, poor DEF quality, or a failed NOx sensor) was ignored for too long, causing the restriction counter to reach zero.

• Tier 4b
• Magnum (180-380)
• Steiger / Quadtrac (350-620)
• Puma (150-220)
• Maxxum (115-150)
• Farmall (110A-140A)
• Axial-Flow series (5130-9240)
• Patriot (2250-4440)
• Titan (3030-4540)

1. 1

   Scan for other active SCR/DEF fault codes (e.g., NOx sensor plausibility, DEF dosing errors, or DEF level warnings) to identify the primary fault triggering the lockout

2. 2

   Verify the DEF tank is not empty and test the fluid quality using a refractometer (urea concentration must be approximately 32.5%)

3. 3

   Inspect the DEF dosing module, lines, and DEF filter for crystallization, leaks, or blockages

4. 4

   Check live data for the upstream and downstream NOx sensors to ensure they are reading accurately and communicating on the CAN bus

1. 1

   Repair the Root Cause

   Fix the primary emissions failure first (e.g., drain and refill contaminated DEF, replace a faulty NOx sensor, or replace a clogged DEF filter).

2. 2

   Connect Diagnostic Tool

   Connect the Case IH Electronic Service Tool (EST) laptop to the machine's diagnostic port.

3. 3

   Access the Engine Controller

   Navigate to the Engine ECM / DCU module in the software.

4. 4

   Reset the Inducement

   Run the 'SCR System Inducement Reset' or 'Restriction Counter Reset' procedure. This tells the ECM that the emissions system has been repaired and resets the restart counter.

5. 5

   Clear Fault Codes

   Clear all inactive fault codes, including 19773.

6. 6

   Verify Repair

   Cycle the ignition key off, wait for the ECM to power down, and then turn the key back on. Verify that the engine starts and the code does not return.