Each diagnostic code consists of the following descriptions: a component identifier (CID), a failure mode identifier (FMI) and an active/inactive status indicator (DIAG). These indicators are shown on the upper display. The CID informs the operator of faulty components. The FMI describes the type of failure that has occurred. When the diagnostic code is active, "DIAG" FLASHES.
Only inactive diagnostic codes are stored in the fault log. An active diagnostic alarm fault becomes inactive when the fault is no longer occurring. An active diagnostic shutdown fault becomes inactive when the fault is no longer occurring and the ECS is turned to OFF/RESET. Active diagnostic alarm faults and diagnostic shutdown faults are indicated when "DIAG" is FLASHING. When the faults become inactive "DIAG" is ON CONTINUOUSLY. The GSC stores a maximum of 12 inactive diagnostic codes in the fault log. If an additional diagnostic code becomes inactive, the GSC automatically clears the earliest inactive diagnostic code. Then, the GSC puts the new inactive diagnostic code in the fault log.
The GSC automatically clears any inactive diagnostic codes that have been stored in the fault log for more than 750 hours. For example, if a CID 190 FMI 3 is logged at 10 hours, then the GSC clears the diagnostic code when the hour meter is at 760 hours. If a CID 100 FMI 4 is logged at 20 hours, then the diagnostic code remains logged until the hour meter is at 770 hours. This feature keeps old diagnostic codes from clogging the fault log, if service personnel have forgotten to clear the log after correcting faults.
When an active diagnostic code changes to an inactive diagnostic code, the GSC will function in the following manner.
- The diagnostic code is recorded in the fault log of the GSC.
- If no other active diagnostic codes are present, then the "DIAG" indicator changes from FLASHING (active diagnostic code) to being ON CONTINUOUSLY. This signifies an inactive diagnostic code.
- The fault alarm indicator or fault shutdown indicator changes from FLASHING to "OFF".
Procedure To View The Fault Log
Note: For a list of all diagnostic codes, see Testing and Adjusting, "Troubleshooting Diagnostic Codes".
Note: Service mode cannot be entered when the ECS is in the AUTO position.
Note: Any active shutdown fault must be made inactive in order to access service mode. A FLASHING shutdown indicator means that a shutdown fault exists. To temporarily change a shutdown fault from an active shutdown fault to an inactive shutdown fault, turn the ECS to the OFF/RESET position. To permanently change a shutdown fault from an active shutdown fault to an inactive shutdown fault, the fault must not be occurring. Also, the ECS must be turned to the OFF/RESET position. If the jumper from terminal 6 to terminal 9 is not installed on the ECS, then the GSC will not power up in OFF/RESET and any active shutdown fault must be corrected before entering service mode.
- Press "SERVICE MODE" key in order to enter service mode. "OP 1" is showing on the lower display. See Systems Operation, "Service Mode" for more information.
- Press "SELECT" key. The diagnostic codes scroll on the upper display if more than one diagnostic code is in the log. Each diagnostic code has the number of occurrences that are showing above the "COUNT" indicator. The lower display shows the hourmeter values of the last occurrence of each fault.
- Press "SELECT" key. The diagnostic codes stop scrolling.
- Press "SCROLL RIGHT" key. If the diagnostic code is logged more than one time, then the first occurrence with a corresponding hourmeter value is showing on the lower display.
- Press "SELECT" key. Diagnostic codes continue scrolling.
- Press "EXIT" key. OP 1 is showing on lower display.
- Press "EXIT" key. The display will return to the normal mode.