Case IH 1816 – Engine Control Unit (Engine ECU) / ISM-DI ENGINE: Capacitor Charge-up Circuit Malfunction (Insufficient Charge)

The Engine Control Unit (ECU) has detected an internal malfunction within its capacitor charge-up circuit. The internal capacitor is failing to reach the necessary voltage level to fire the injectors properly, which typically forces the engine into a derated mode or causes a shutdown.

• skid steer
• Skid Steer Loaders (SR130, SR160, SR175, SR175B, SV series)
• Compact Track Loaders (TR and TV series)

1. 1

   Stop the engine and let it cool completely before starting work.

2. 2

   Check for water ingress or debris inside the ECU and injector connector terminals (often caused by pressure washing).

3. 3

   Inspect the engine wiring harness for chafing, open circuits, or shorts to ground.

4. 4

   Test the fuel injectors for internal coil shorts or terminal shorts, which can draw excessive current and drain the ECU's capacitor.

5. 5

   Perform an 'Injector Electrical - Dynamic Test' using the CNH Electronic Service Tool (EST) to isolate faulty injectors or wiring.

1. 1

   Disconnect Power

   Disconnect the battery before servicing the electrical system.

2. 2

   Repair Wiring/Injectors

   If the diagnostic checks reveal a shorted wiring harness or a shorted fuel injector, repair the wiring or replace the faulty injector first.

3. 3

   Replace the ECU

   If the wiring and injectors test perfectly fine, the fault is an internal hardware failure of the capacitor inside the Engine ECU. The Engine ECU must be replaced.

4. 4

   Program Injector QR Codes

   When installing a new Engine ECU, you must use the CNH EST diagnostic tool to write the 30-character alphanumeric Injector ID codes (QR codes) from the installed injectors into the new ECU. If these codes are not registered correctly, the engine will suffer from rough idling, knocking noise, and poor performance.

5. 5

   Pump Relearn

   After programming, run the engine and allow sufficient time (several minutes) for the new ECU to learn the performance parameters of the fuel supply pump. Clear any inactive fault codes.