793F CMD Off-Highway Truck/Tractor Braking System Caterpillar

This functional test is used as an aid in troubleshooting. This test is used to verify the operation of the automatic retarder control system (ARC). The machine must be stationary. The control valves are activated. Service personnel should monitor the service brake pressure for the correct operation.

If a problem exists with the retarder system of the machine, perform the following procedure:

Illustration 1	g00538815
Cat ET screen for the ARC system test

1. Procedure

   1. Ensure that the manual retarding (retarder lever) is operational.

   2. Initiate the "Cat Elcetronic Technician (Cat ET)" service tool.

   3. Select the "Brake ECM".

   4. Select "Service" from the drop-down menu.

   5. Click on the "Start" button to begin the test.

      The control valve gradually allows full brake system oil to flow during the test. Then, the control valve will gradually stop the flow of brake system oil. The cycle is then repeated. The ARC will gradually increase the pressure of the service brakes to full pressure. The ARC will then decrease the pressure of the service brakes to zero.

      Note: The test of the automatic retarder will terminate if a fault is detected during the test.

   6. Follow the instructions that are being displayed on the Cat ET screen to complete this procedure.