E04 fault in ABB DCS800 drive indicates SDCS-CON-4 RAM memory test error. This means an issue with the RAM on the control board, which could be due to a hardware fault or corruption that prevents the drive from properly accessing memory resources.

Here’s a troubleshooting approach for an E04 fault:

1. Power Cycle the Drive:

   • Start by fully powering down the drive, waiting a few minutes, then turning it back on. This may clear minor memory-related issues if they are temporary.

2. Check Connections to the SDCS-CON-4 Board:

   • Ensure all connectors and cables attached to the SDCS-CON-4 control board are secure. Loose connections could sometimes trigger RAM access errors.

3. Reload Firmware (If Possible):

   • Obtain the correct firmware version for the DCS800 and follow ABB’s procedures to reload it. Sometimes reloading the firmware can help resolve RAM-related issues if they stem from corrupted data rather than hardware.

4. Inspect and Test the Control Board:

   • If you have access to diagnostic tools, run any available memory tests to check the RAM’s integrity. If the issue persists, the RAM on the SDCS-CON-4 board may be damaged.

5. Replace the SDCS-CON-4 Control Board:

   • In cases where the RAM error cannot be cleared, replacing the SDCS-CON-4 control board may be necessary, as the fault likely indicates a hardware problem that cannot be resolved by software.