GUIDE AS 5V3042 - Caterpillar

Diagnostic codes are associated with failed electrical components or circuits that provide information to the PRCM. Diagnostic codes are also associated with failed electrical components or circuits, that receive information from the PRCM. The diagnostic code closely identifies the cause of the failure.Each diagnostic code consists of the following items: a component identifier (CID), a failure mode identifier (FMI) and a fault indicator ("DIAG"). These items are shown on the upper display. A fault indicator can be active or inactive. The CID identifies the component that has failed in the system. The FMI describes the nature of the problem. When the "DIAG" indicator is FLASHING, the diagnostic code is active. This means that the diagnostic code is present. When the "DIAG" indicator is ON CONTINUOUSLY, the diagnostic code is inactive and the CID FMI is recorded in the fault log. See Systems Operation, "Diagnostic Code Viewing and Clearing" in order to view the fault log. When the "DIAG" indicator is not showing, there are NO diagnostic codes that are detected or recorded. Service personnel interpret the identifiers in order to assist with troubleshooting.The PRCM has a fault log to help with troubleshooting of diagnostic codes. Inactive diagnostic codes (CID FMI) are recorded in the fault log for viewing at a later time. Also, the number of occurrences are totalled and the number of occurrences are shown on the upper display with the CID and the FMI. During troubleshooting, it is sometimes necessary to disconnect the harness connector from the PRCM and a diagnostic code of CID 0590 FMI 09 is created. An FMI 09 describes the voltage that is above normal. This fact is also used as an aid in the troubleshooting process. Clear these created diagnostic codes after the particular problem is corrected and the diagnostic code is cleared.Note: The CID 590 FMI 09 will NOT be logged if the setpoint "P03" is set to "01". Refer to Systems Operation, "Setpoint Viewing and Programming".
Table 1
DIAGNOSTIC CODES for the PRCM    
For troubleshooting, see the procedure with the same CID and FMI.    
CID / FMI     Description    
CID 0248 CAT data link:    
FMI 11     Short to + Battery or a short to - B of either CAT data link wire.    
CID 0268 PRCM Internal Memory:    
FMI 02     Signal out of range.    
CID 0333 Relay Driver Module (A):    
FMI 03     Voltage above normal.    
FMI 04     Voltage below normal.    
CID 0334 Relay Driver Module (B):    
FMI 03     Voltage above normal.    
FMI 04     Voltage below normal.    
CID 0477 PRCM Output Relay (1):    
FMI 03     Relay coil open circuit.    
FMI 04     Relay