TUBE AS 4617480 - Caterpillar

Table 1
AL Fault Code Troubleshooting    
AL Fault Code    Description    Troubleshooting    
AL1     High Water Temperature Alarm
Coolant temperature increases to within
6°C (11°F) of setpoint P15.     See the Troubleshooting, "Troubleshooting Dedicated Shutdown Indicators".    
AL2     Low Engine Coolant Temperature Alarm
Coolant temperature decreases to setpoint P16.     See the Troubleshooting, "Troubleshooting Dedicated Shutdown Indicators".    
AL3     Low Engine Oil Pressure Alarm
Oil pressure drops to within
34 kPa (5 psi) of the P13 or P14 setpoint.     See the Troubleshooting, "Troubleshooting Dedicated Shutdown Indicators".    
AL4     Fault Detected By Engine ECM
The engine ECM detects an alarm fault or a shutdown fault.     Refer to the appropriate engine troubleshooting service manual.    
Illustration 1 g00442245
Upper Display With AL Fault Code AL3 ShowingAL Fault Codes are shown as "AL1" through "AL4" on the upper display. The fault codes include specific engine fault conditions. An example of a specific engine fault condition is the low engine oil pressure alarm. An example of a protective relaying function is the underfrequency fault.AL fault codes depend on certain setpoints. For more information on setpoints, see the Systems Operation, "Service Mode". AL fault codes are not diagnosed by the GSC. These codes are not stored in the fault log. Many of the AL fault codes are programmable as a fault alarm or as a fault shutdown. The AL fault codes are accompanied by either the fault alarm indicator or the fault shutdown indicator on the GSC in order to show the severity of the fault.