Case IH 17918 (F-3696-00) - ECU – Engine Control Unit (ECU) / Engine Control Module (ECM): Number of manual catalyst management events requested via vehicle display exceeded the limit.

This is an operational/software limit code indicating that the operator has requested too many manual Diesel Particulate Filter (DPF) / catalyst regenerations via the tractor's instrument cluster or display, exceeding the programmed limit.

• VESTRUM CVX
• Case IH / CNH Stage V MR (Medium Range) equipment
• Case IH Farmall 40, 45, and 50 Tractors with Cab and CVT Transmission

1. 1

   Check for related interruption code 17917, which indicates that manual catalyst management events have been interrupted too many times by the operator.

2. 2

   Investigate the root cause of frequent manual regeneration requests (e.g., tractors doing light work or short runs often fail to reach exhaust temperatures required for passive regeneration).

3. 3

   Check for sensor faults, such as code 17923 (Differential pressure sensor: hoseline connection failure), which can falsely report a clogged DPF and prompt unnecessary regenerations.

4. 4

   Use a diagnostic tool to read the actual soot load and differential pressure across the DPF to verify if the filter is genuinely restricted.

1. 1

   Connect Diagnostic Software

   Connect a dealer-level diagnostic tool (such as CNH Electronic Service Tool (EST) or a compatible multi-brand tool like Jaltest).

2. 2

   Reset DPF Counters

   Navigate to the engine ECU parameters and perform a reset of the DPF regeneration levels/counters. This will clear the software lockout that triggered the code.

3. 3

   Perform a Forced Service Regeneration

   If the diagnostic tool shows that the DPF is loaded with soot, initiate a forced stationary service regeneration via the software (since the manual display method is locked out). Ensure the tractor is parked safely with the handbrake on, PTO disengaged, and hydraulic system inactive.

4. 4

   Operator Education

   Instruct the operator to allow the tractor to perform passive regenerations by running it under higher loads (e.g., 30 minutes of heavy draft work) and to avoid interrupting manual regenerations once they have started.

5. 5

   Clean or Replace DPF (If Necessary)

   If the forced regeneration fails or the DPF is completely blocked with ash/soot, the DPF must be removed for professional cleaning or replacement.