Case IH 3739 – Engine Control Module (ECM) / Electronic Diesel Control (EDC): Power stages, Injector: Loss of synchronization sending bytes to the MM from CPU

This code indicates a critical internal hardware or software failure within the engine's control module. Specifically, the module's Central Processing Unit (CPU) has lost synchronization while attempting to transmit data bytes to the internal memory module (MM) regarding the fuel injector power stages.

• Farmall
• Steiger
• Magnum
• Puma
• Maxxum
• 240 Series Axial-Flow Combines
• SR175
• SR200

1. 1

   Ensure the ECM/EDC is receiving proper and stable voltage to rule out voltage spikes or severe drops causing processor synchronization errors

2. 2

   Use the Case IH Electronic Service Tool (EST) to clear the fault code, cycle the key, and operate the machine to see if the code returns

3. 3

   Check for accompanying injector power stage codes (e.g., 3740, 3741, 3742) which indicate further internal SPI errors or response time faults

1. 1

   Disconnect battery

   Disconnect the machine's battery to prevent electrical arcing.

2. 2

   Locate ECM

   Locate the EDC/ECM on the engine block or firewall (location varies by model).

3. 3

   Disconnect wiring

   Carefully disconnect the main wiring harness connectors from the ECM.

4. 4

   Remove ECM

   Unbolt and remove the faulty ECM.

5. 5

   Install new ECM

   Install the new OEM ECM and reconnect the wiring harnesses.

6. 6

   Reconnect battery

   Reconnect the battery.

7. 7

   Program ECM

   Connect the Case IH Electronic Service Tool (EST) laptop to the machine's diagnostic port. You must use the EST to flash the correct firmware for the specific machine and perform the procedure to 'Restore Self Learning Parameters' (injector trim codes, immobilizer sync, etc.).