Case IH 19778 – Engine Control Module (ECM): Maximum engine starts reached

This is an emissions-related inducement (lockout) code indicating that a primary fault occurred within the SCR/DEF system. The machine was operated until the countdown was completely exhausted without the root cause being repaired, locking the engine from starting or forcing it into a severe derate (Creep mode).

• Tier 4b
• Case IH T7 Series Tractors (Tier 4B)
• Case N-Series Loaders / Backhoes (Tier 4 Final)
• Other CNH agricultural and construction equipment utilizing the same Tier 4 SCR architecture.

1. 1

   Scan for active primary codes using a diagnostic tool to identify the primary SCR fault that triggered the inducement (e.g., DEF pump failure, NOx sensor plausibility, or DEF dosing module errors).

2. 2

   Check DEF fluid levels and quality to ensure the tank is not empty and the fluid is not contaminated or degraded.

3. 3

   Inspect SCR components, including wiring harnesses for the DEF injector, DEF supply module, and upstream/downstream NOx sensors for physical damage.

1. 1

   Repair the Root Cause

   Address the primary SCR system failure identified during your diagnostic checks (e.g., replace the failed NOx sensor, thaw frozen DEF lines, or replace the DEF supply pump).

2. 2

   Refill DEF

   If the inducement was caused by running the DEF tank dry, refill the tank with fresh, high-quality Diesel Exhaust Fluid.

3. 3

   Connect Diagnostic Tool

   Connect the CNH Electronic Service Tool (EST) to the machine's diagnostic port.

4. 4

   Clear Primary Codes

   Once the physical repair is complete, clear the primary SCR fault codes.

5. 5

   Perform SCR Inducement Reset

   Navigate to the special procedures menu in the CNH EST software and execute the SCR Inducement Reset (or Engine Start Counter Reset) routine. This will reset the ECM's internal counter, clear code 19778, and restore normal engine starting and power.