PUMP 6V6025 - Caterpillar

addition to the normal duties of retarding the machine, the Automatic Retarder Control (ARC) is constantly checking most of the inputs and outputs for the correct operation. The ARC shows diagnostic information on the display in order to assist with troubleshooting. The list below shows The diagnostic information that is on the ARC'S display.
The ARC shows a number of faults.
The status of the inputs and the outputs
The engine speed
The control speed value
The number of cycles of the control valveService personnel select diagnostic information by placing the display in a specific mode. Refer to Testing and Adjusting, "Using Service Display Mode to Determine Diagnostic Codes".The display of the ARC notifies the operator of any system faults. The ARC disables the automatic retarding. The ARC flashes the retarder lamp when a fault happens. The retarder lamp continues to flash and the automatic retarding remains disabled until the switch for the ARC is turned off. Note: If automatic retarding is disabled, manual retarding with the retarder lever remains functional.Whenever the machine is at rest the ARC checks the output of the solenoid circuits and the ARC briefly activates the solenoids. This check shows if the solenoids are present and operational. While the solenoids are being activated the solenoids make a clicking and hissing noise that can be heard.