Troubleshooting the E-48 GMU/VIU Communication Loss (Critical) Error Code

Overview

E-48 is a critical communication error that occurs when the fryer control detects a loss of communication or a configuration mismatch between connected components.

E-48 – GMU Communication Loss (Critical)

The control has detected that the GMU and/or vat type information has been lost, changed, or is no longer communicating correctly. Possible causes:

• CAN Bus Cable or Routing issue

• Incorrect GMU magnet positions

• Failed GMU

E-48 – VIU Communication Loss (Critical)

The control has detected that the control panel (VIU) address has been lost or changed. Possible causes:

• CAN Bus wiring issue

• Loose or damaged J26 connection

• Incorrect GMU magnet positions

• Failed control panel (VIU)

• Broken jumper connections in the VIU cable

• Failed jumper-detection circuit within the control panel resulting in a fryer configuration mismatch

E-48 – OMS Communication Loss (Critical)

The control has detected that the OMS Bord and/or vat type information has been lost, changed, or is no longer communicating correctly. Possible causes:

• CAN Bus Cable or Routing issue

• Failed OMS

Call Avoidance

Before dispatching a technician, perform the following checks:

1. Turn the fryer power switch OFF.

2. Wait 30 seconds.

3. Turn the fryer power switch ON.

4. Verify whether the E-48 error clears.

If the error remains after these steps, field service is required.

Field Troubleshooting

Recommended Parts

For E-48 GMU:

• CAN Cables

• GMU Board

• GMU Config Magnets

For E-48 VIU:

• CAN Cables

• Display Control Panel (VIU)

• Jumper Position Dongle

For E-48 OMS:

• CAN Cables

• OMS Board

Recommended Tools:

• Digital Multimeter

• CAN Cable Tester

• Basic hand tools (screwdrivers, nut drivers, etc.)

E-48 GMU Troubleshooting

1. Cycle power OFF and ON.

   • If the error clears and does not return, repair is complete.

   • If the error returns, go to Step 2.

2. Check the Blue lights on the GMU.

   • If blue lights are bright, the GMU has locked up, replace GMU.

   • If no lights are on the GMU, verify 24 VDC power to GMU from power distribution board and power supplies.

   • If blue lights are dim, the GMU has power and is not in a locked state, go to Step 3.

3. Inspect CAN cable wiring on the GMU:

   1. Test the cables using the cable tester.

   2. Check for loose, disconnected, damaged, or pinched wires. If wiring issues are found, repair or replace the wiring, then retest.

   3. Verify CAN cable routing is correct.

   If no wiring issues are found, go to Step 4.

4. Verify fryer configuration settings match the installed hardware.

   1. If configuration is incorrect, factory reset ONLY the far-left control.

      The original configuration is on the far-left control and may not of communicated properly if any boards were replaced.

   2. If configuration is correct, go to Step 5.

5. Verify magnets are installed in the correct locations for the fryer configuration.

   1. If magnet positions are incorrect, correct them and retest.

   2. If magnet positions are correct, replace GMU.

E-48 VIU Troubleshooting

1. Cycle power OFF and ON.

   • If the error clears and does not return, repair is complete.

   • If the error returns, go to Step 2.

2. Inspect CAN cable wiring on the rear of the control:

   1. Test the cables using the cable tester.

   2. Check for loose, disconnected, damaged, or pinched wires. If wiring issues are found, repair or replace the wiring, then retest.

   3. Verify CAN cable routing is correct.

   If no wiring issues are found, go to Step 3.

3. Inspect the J26 connector on the rear of the control panel.

   1. Verify the J26 connector is fully seated.

   2. Check for bent pins, corrosion, or damaged wiring. If defects are found, repair and retest.

   3. If the connector is good, go to Step 4.

4. Verify fryer configuration settings match the installed hardware.

   1. If configuration is incorrect, factory reset ONLY the far-left control.

      The original configuration is on the far-left control and may not of communicated properly if any boards were replaced.

   2. If configuration is correct, Replace Display Control Panel.

E-48 OMS Troubleshooting

1. Cycle power OFF and ON.

   • If the error clears and does not return, repair is complete.

   • If the error returns, go to Step 2.

2. Check for lights on the OMS board.

   If no lights are on the OMS board, verify the Line voltage and 24 VDC power to the OMS Board from power distribution board and power supplies.

   If lights are present, the OMS has power, go to Step 3.

3. Inspect CAN cable wiring on the OMS:

   1. Test the cables using the cable tester.

   2. Check for loose, disconnected, damaged, or pinched wires. If wiring issues are found, repair or replace the wiring, then retest.

   3. Verify CAN cable routing is correct.

   If no wiring issues are found, go to Step 4.

4. Verify fryer configuration settings match the installed hardware.

   1. If configuration is incorrect, factory reset ONLY the far-left control.

      The original configuration is on the far-left control and may not of communicated properly if any boards were replaced.

   2. If configuration is correct, Replace the OMS Board.