GUARDRAIL AS 4772670 - Caterpillar

Illustration 1 g00427558
Diagnostic Example (1) First display. (2) Second display. (3) Module identifier (MID). (4) Service code indicator ("SERV CODE"). (5) Component identifier (CID). (6) Failure Mode identifier (FMI). Service mode is mode 3. The main display module detects faults that occur with sensor inputs, sender inputs, and main display module outputs while the main display module is in normal mode. The signal is at the contact of the main display module. A diagnostic code is detected when the signal is outside a valid range. The main display module then records the diagnostic code. The diagnostic code remains stored for future reference when the fault is not present. The main display module detects faults and the main display module diagnoses faults in the following circuits:
Display output modules
Action alarm output
Action lamp output
Sensor input
Harness codeNote: The main display module does not detect switch input faults.Service personnel can see the diagnostic codes and service personnel can troubleshoot the diagnostic codes when the main display module has detected a fault. All detected faults are shown in the display area as a diagnostic code. The diagnostic codes can be placed on hold and the diagnostic codes can be cleared while the main display module is in service mode. Note: Diagnostic codes from other machine systems under electronic control are shown in the display area of the main display module when the main display module is in Service Mode. The CAT data link allows the transfer of diagnostic information from other electronic control modules to the main display module. This diagnostic information is then shown when the main display module is in service mode. The diagnostic code for faults from other electronic control modules has a MID that is unique to the control. These diagnostic codes can scroll similarly to the diagnostic codes from the Caterpillar Monitoring System. See the following description of Module Identifier (MID).The diagnostics of the Caterpillar Monitoring System are available to assist with the troubleshooting of diagnostic codes when the main display module is placed in service mode. A diagnostic code is used to specify each fault. The diagnostic code is made up of three identifiers (MID, CID and FMI). These identifiers are shown in the display area. The display area continuously changes between the following identifiers when the diagnostic code is on hold: Module Identifier (MID) - The MID is a three-digit code that is shown on the display area. The MID is shown for approximately one second before the diagnostic code that is shown in the same area. The electronic control module that has diagnosed the diagnostic code is logged by the MID. The following examples are of some MID. Caterpillar Monitoring System ... 030 Engine Control (ADEM) ... 036 Power Train Electronic Control System ... 081 All Wheel Drive Electronic Control System ... 075See the table for the Module Identifier (MID) on the Electrical System Schematic for the machine that is being serviced for the most complete list. To troubleshoot diagnostic codes, use the service manual