SPACER 3N2345 - Caterpillar

Illustration 1 g01402302
Schematic for the service brake oil pressure switchThis diagnostic code is associated with the service brake oil pressure switch. The switch is connected to two inputs of the Power Train/Chassis Electronic Control Module (ECM). One contact is open and the other contact is grounded during proper operation.This FMI 03 means that the ECM has determined that the normally open contact and the normally closed contact are open.Note: The following test procedure may create other diagnostic codes. Ignore these diagnostic codes and clear the diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 0298 FMI 03 is active before performing this procedure.Test Step 1. CHECK THE GROUND CIRCUIT OF THE SWITCH IN THE HARNESS
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the machine harness connector from the switch.
Measure the resistance between frame ground (wire 202-BK) of the machine harness and the contact A (wire 202-BK).Expected Result:The resistance is less than 5 ohms.Results:
YES - The resistance is less than 5 ohms. The circuit is correct. Proceed to Test Step 2.
NO - The resistance is greater than 5 ohms. The circuit is open. The machine harness has failed.Repair: Repair the machine harness or replace the machine harness.STOPTest 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 J1-34 (wire F790-BR) and J1-33 (wire F787-GN) 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 5 ohms.Results:
YES - Each resistance measurement is greater than 5 ohms. Proceed to Test Step 3.
NO - One or more of the resistance measurements are less than 5 ohms. The harness has failed. The short is between J1-34 (wire F790-BR) and the circuit with the lowest resistance or the short is between J1-33 (wire F787-GN) and the circuit with the lowest resistance.Repair: Repair the wiring harness or replace the wiring harness.STOPTest Step 3. CHECK THE SWITCH CIRCUITS IN THE HARNESS
The machine harness remains disconnected from the ECM and the switch.
At the harness connector for the switch, connect a jumper wire between contact B (wire F787-GN) and contact C (wire F790-BR).
At the harness connector for the ECM, measure the resistance from contact J1-34 (wire F790-BR) to contact J1-33 (wire F787-GN).Expected Result:The resistance is less than 5 ohms.Results:
YES - The resistance is less than 5 ohms. Proceed to Test Step 4.
NO - The resistance is greater than 5 ohms. The circuit is open.Repair: The machine harness has failed. Repair the machine harness or replace the machine harness.STOPTest Step 4. CHECK THE OPERATION OF THE SWITCH
The machine harness remains disconnected from the switch.
Connect one lead from a multimeter to contact A of the harness connector on the switch.
Connect the other lead from a multimeter to contact B of the harness connector on the switch.
Measure the resistance