SUPPORT AS-FAN 2302946 - Caterpillar

In addition to this procedure, the auto retarder pressure circuit can be checked by monitoring the auto retarder indicator of the display. If the indicator is "On" that means the auto retarding is active. If the indicator is "Off" that means the auto retarding is not active.Note: In addition to this procedure, the status of the auto retarder pressure circuit is shown when the display is in the input status mode (mode 2).This diagnostic code is recorded when the ARC detects the presence of pressure for the AUTO retarder. Simultaneously, the supply solenoid has not been activated and the control solenoid has not been activated. The switch is open. The circuit of the AUTO retarder pressure switch connects to connector A-A16 (wire D991-OR-16).Note: Ensure that the CID 0714 FMI 03 is present and active.
CHECK THE SWITCH.
Turn the disconnect switch and the key start switch to the ON position.
Place the display into the detected fault mode (mode 1).
Ensure that the diagnostic code is active.
Observe the "On/Off" status of the fault present indicator.
Temporarily connect wire (D991-OR-16) to wire (202-BK-16) at the pressure switch. Expected Result: The diagnostic code remains active. The diagnostic code does NOT change.Results:
OK: The diagnostic code remains in the active state. The diagnostic code does NOT change. The machine harness is faulty or the ARC is faulty. Proceed to Step 2.
NO: The diagnostic code changes from being active to being NOT active. The pressure switch is failed. Repeat this test "CHECK THE SWITCH" in order to verify that the switch has failed. Replace the AUTO retarder pressure switch. STOP.
CHECK THE GROUND CIRCUIT.
Remove the wire connections of the previous test "CHECK THE SWITCH".
Observe the status of the diagnostic code. The diagnostic code is active or the diagnostic code is NOT active.
At the pressure switch, place a jumper from wire 202-BK-16 to frame ground.
View the status of the diagnostic code.Expected Result: The diagnostic code remains active.Results:
OK: The diagnostic code remains active. Wire D991-OR-16 or the ARC is faulty. Proceed to Step 3.
NO: The present indicator changes from "On" to "Off". The diagnostic code is NO longer active. Wire 202-BK-16 is open in the machine harness. The open is between the pressure switch and frame ground. Repair the machine harness or replace the machine harness. STOP.
CHECK THE SWITCH CIRCUIT.
Turn the key start switch and the disconnect switch to the OFF position.
The jumper of the previous test "CHECK THE GROUND CIRCUIT" remains intact.
Disconnect the machine harness (A) from the ARC.
Measure the resistance between contact A-A16 (wire D991-OR-16) and frame ground.Expected Result: The resistance is less than 5000 ohms.Results:
OK: The resistance is less than 5000 ohms. The resistance of the harness circuit is correct. It is unlikely that the ARC is faulty. Exit this procedure and perform a check of the CID and the FMI again. Replace the ARC, if the cause of the diagnostic code is not found. See Testing And Adjusting, "ARC - Replace". STOP.
NO: The resistance is greater than 5000 ohms. The machine harness is faulty. Wire D991-OR-16 is