Case IH 3847 – ENGINE ECU / EDC (Electronic Diesel Control): Injector - Zero Fuel Calibration by Lambda (ZFL): DFC reporting error state on comparing energizing time to Max value injector 4.

The engine control module is attempting to perform a Zero Fuel Calibration (ZFC) on cylinder 4, but the electrical energizing time required for the injector to respond has exceeded the maximum allowable limit. This indicates a plausibility error in the energizing times, which typically points to a failing fuel injector (Injector 4), a wiring issue to that specific injector, or a localized fuel delivery problem.

• Farmall
• Farmall 65A
• Farmall 75A
• Farmall 115U
• Maxxum
• Puma
• Quantum
• SR200
• SR220
• SR250
• SV250
• SV300
• TR270
• TR320
• TV380

1. 1

   Check Fuel Pressure: Apply a load to the engine (using hydraulics over relief, hydrostatic stall, or a dynamometer) and run it at rated RPM. If the fuel pressure drops below 0.276 bar (4.0 psi) at any time, the low-pressure fuel system is compromised.

2. 2

   Check for Air in the Fuel System: Install a test line constructed with clear tubing to observe if air is entering the system.

3. 3

   Inspect Filters and Lines: Check and replace the fuel pre-filter and main fuel filter(s) if necessary. Inspect Voss O-ring fittings for leaks.

4. 4

   Inspect the Fuel Tank and Lift Pump: Check the bottom/sidewalls of the tank for debris and clean as required. Ensure the lift pump valve assembly is properly connected.

5. 5

   Check Wiring: Verify the wiring harness and electrical connectors going to Injector 4 for chafing, corrosion, or poor pin fitment.

1. 1

   Perform preliminary diagnostic checks

   Perform the preliminary diagnostic checks to ensure the engine is receiving adequate, air-free fuel.

2. 2

   Reload Engine Dataset

   If the fuel supply is good but the fault persists, connect the diagnostic service tool and Reload Engine Dataset to see if the calibration error clears.

3. 3

   Replace Injector 4

   If reloading the dataset does not resolve the issue, replace Injector 4, as its internal solenoid or mechanical components have degraded beyond the maximum energizing time threshold.

4. 4

   Program new injector IMA code

   When installing the new injector, use the diagnostic service tool to enter the new injector's 9-digit IMA coding into the EDC so the module can learn the new injector's flow characteristics.

5. 5

   Restore self-learning parameters

   If the EDC itself is deemed faulty and replaced, follow the appropriate service tool procedure to restore all self-learning parameters.