How to determine what CM4000 or CM3000 issue occurred to cause the red wrench LED to turn on?



Need to diagnose the cause of a maintenance error after the red maintenance LED illuminates.

Product Line
CM3000 & CM4000 Series

Front Display or Modbus Registers

It is required to be able to determine the CM series error in order to provide troubleshooting solutions.

The red maintenance LED, located next to the wrench symbol on the circuit monitor, indicates a potential hardware or firmware problem in the circuit monitor.

Options available to determine error code:
1. With a display: navigate to Main Menu>Diagnostics>Maintenance LED. This will provide the applicable error message(s).

2. Using software: see the attached CM3&4 Register List, specifically registers 3050 and 3051 as these will indicate an error and which component of the meter is affected. In addition, the Register-Based Diagnostic Error Log can be viewed starting on register 380 (register range 380-500; ordered from most recent event to oldest) - see the 'Misc Control Reg' Tab.

Often, a firmware upgrade or reinstall will resolve most maintenance issues. For instructions on upgrading the firmware, please see article FA237920. If the error is noted as a continuous reset, try to power cycle the unit. However, if the maintenance LED remains illuminated after these attempts, the unit may need to sent in for repair or replacement.