GSC ALARM INDICATORS AND FAULT CODE TROUBLESHOOTING - Continued
Dedicated Shutdown Indicators
Starts flashing when alarm condition is detected. Lights continuously after
Fault Shutdown Indicator
Flashes to indicate system was shut down due to a fault.
Fault Alarm Indicator
Flashes to indicate an alarm condition. Component Identifier (CID) and
Failure Mode Identifier (FMI) codes will be displayed on the upper display to
identify what is wrong. The CID identifies the component that has a problem,
the FMI describes the nature of the failure.
Flashes while there is an active Alarm condition. The diagnostic code should
Lights continuously when there is an inactive alarm condition or inactive
shutdown condition. The diagnostic code is inactive and the CID and FMI
were recorded in the Fault Log.
If not lit, there are no diagnostic codes available.
There are two basic types of faults: Active and Inactive. An active fault is one that is occurring now, an inactive fault
is a fault that has occurred previously.
GSC diagnostic codes are associated with failed components or circuits that provide information to the GSC or that
receive information from the GSC. Each diagnostic code consists of the following:
A component identifier (CID) code
A failure mode identifier (FMI) code
The DIAG indicator lit
Two types of faults have diagnostic codes associated with them: alarm faults and shutdown faults. When a fault
occurs that has a diagnostic code associated with it, the DIAG indicator flashes, then the GSC flashes either the
fault alarm indicator, or the fault shutdown indicator. For a shutdown fault, the CID and FMI are shown on the upper
display immediately. For a fault alarm: the ALARM CODES key must be pressed; then the CID and FMI are shown
on the upper display. A flashing DIAG indicator means that the fault is presently active. When the DIAG indicator is
on continuously, the fault occurred previously.
DIAGNOSTIC EVENTS AND EVENT CODES
The GSC also displays codes for diagnostic events. These event codes are in the same format as the fault codes
and they can be active events and may be logged. The Symptom/Malfunction Index and troubleshooting tables
show these event codes in sequence with fault codes. Often event codes are related to fault codes and the
troubleshooting associated with them. Diagnostic events can be logged in the ENGINE CONTROL Module (ECM)
and used to investigate engine malfunctions. Event codes indicate problems with the engine performance and are
symptoms to be investigated. They can also relate directly to required maintenance services or actions.