WASHER GP-WINDOW 4715643 - Caterpillar

brake/cooling ECM controls the operation of the manual retarder. The manual retarder is used by the operator when the automatic retarder control (ARC) is not desired. For example, the operator desires to retard the machine at an engine speed that is slower than the engine speed that is used by the ARC.The ECM reads the position of the retarder lever. The ECM will then actuate the solenoids in order to engage the service brakes. The same solenoids that are used by the ARC to command braking are used by the manual retarder function to command braking. The larger command will be applied to the solenoids.