CHAIN AS 2425318 - Caterpillar

Illustration 1 g00864991
Schematic for the Parking Brake Pressure SwitchThis diagnostic code is associated with the parking brake pressure switch. The switch is connected to two inputs of the ECM. The inputs are "Normally Open" and "Normally Closed". One of the inputs is open and the other input is grounded during proper operation.The FMI 04 means that the ECM has determined that the "Normally Open" and "Normally Closed" circuits are grounded.Note: The following test procedure may create other diagnostic codes. Ignore these diagnostic codes and clear these diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 0627 FMI 04 is active before performing this procedure.Test Step 1. CHECK THE SWITCH
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the machine harness from the switch.
Turn the key start switch and the disconnect switch to the ON position.Expected Result:The CID 0627 FMI 04 has been replaced by CID 0627 FMI 03.Results:
OK - The CID 0627 FMI 04 has been replaced by CID 0627 FMI 03. The machine harness and the ECM are correct. Proceed to Test Step 3.
NOT OK - The CID 0627 FMI 04 is still active. Proceed to Test Step 2.Test Step 2. CHECK THE HARNESS
Turn the disconnect switch and the key start switch to the OFF position.
The machine harness remains disconnected from the switch.
Disconnect the machine harness connector(s) from the ECM.
Measure the resistance between contacts J1-27 (wire G764-PK) and J1-36 (wire 419-YL) of the machine harness to all the contacts that are used in machine harness connectors for the ECM.Expected Result:Each resistance measurement is greater than