Troubleshooting the E-255 Riot System Communication Loss Error Code

Overview

The E-255 error code indicates a communication failure between the Wi-Fi radio and the Riot radio system. This occurs when the radio is powered but does not receive any communication packets from the control for five minutes. When this happens, the system logs an E-255 error: "Controller Communications Disconnected" in the Riot event log.

NOTE: This error is not visible to the user, and it is not recorded in the error log or activity logs on the fryer. It is only detectable from the Riot system interface.

Call Avoidance

To help the end user resolve the issue without a service call:

Check power sources: If one control is not functioning or not powered but the Wi-Fi radio is powered by another VAT’s power cord, this may cause the issue. Make sure the power connections are correct and secure.

Field Troubleshooting

If call avoidance steps do not resolve the issue, proceed with the following field troubleshooting steps.

Recommended Parts:

• Control board

• Display control RS-485 communication cable

• Wi-Fi radio module

• Wi-Fi radio antenna

Recommended Tools:

• Basic hand tools

• Multimeter

• Zip ties

Troubleshooting

1. Verify power to the Wi-Fi radio.

2. If the radio is not powered, check the power source.

3. Inspect RS-485 cable connection at the control board.

• If the cable is disconnected or loose, reconnect it securely.

• If connected, continue at Step 4.

4. Inspect RS-485 cable connection at the radio board.

• If the cable is disconnected or loose, reconnect it securely.

• If connected, continue at Step 5.

5. Test continuity of the RS-485 cable.

• If the cable fails continuity, replace it.

• If the cable passes, continue at Step 6.

6. Replace the control board. If the issue persists, continue at Step 7.

7. Replace the Wi-Fi radio module. After replacement, monitor for communication restoration.

Other Scenarios

• Split Power Source Issue: If the fryer has multiple VATs, one control may be off while the Wi-Fi radio remains powered by another VAT. This can cause communication loss.

• Intermittent RS-485 Failures: Rare cases may involve intermittent faults in the RS-485 cable or connectors. Use a multimeter to test for stable resistance and continuity.