DRIVE GP-FINAL 3417668 - Caterpillar

Illustration 1 g03326688
Connections of the secondary brake solenoid
The CID 0722 diagnostic code is associated with the secondary brake solenoid. The circuit is connected to an ON/OFF output of the Power Train ECM. The FMI 03 means that the Power Train ECM has determined that voltage is present in the circuit and no voltage should be present.The service brake switch is depressed when the service brake pedal is fully depressed. When the switch is depressed, system voltage is directed to the secondary brake solenoid through fuse 9 and the switch contacts. Then, the secondary brake is engaged. The resistance of the solenoid coil is approximately 42 ohms at 25° C (77° F). The resistance will increase as the temperatures increase.The possible causes of this diagnostic code are listed:
The switch has failed.
The energize circuit of the solenoid is shorted to another voltage source.
The ECM has failed. An ECM failure is unlikely.Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear these diagnostic codes when the original diagnostic code has been corrected. Ensure that the 0722 FMI 03 diagnostic code is active before performing this procedure.Note: Before performing this procedure, inspect the harness connectors that are involved in the circuit. Poor connections can often be the cause of a problem in an electrical circuit. Verify that all connections in the circuit are clean, that all connections are secure, and that all connections are in good condition. If a problem with a connection is found, correct the problem and verify that this diagnostic code is active before performing this procedure.Note: Use a digital multimeter for the measurements in this procedure.Test Step 1. CHECK THE SWITCH
Turn the key start switch and the disconnect switch to the OFF position.
At the fuse panel, remove fuse 9 from the fuse holder.
Turn the disconnect switch and the key start switch to the ON position. Do not start the engine.
Observe the status of the CID 0722 FMI 03 diagnostic code.Expected Result:The CID 0722 FMI 03 diagnostic code is no longer active when the fuse is removed.Results:
OK - The CID 0722 FMI 03 diagnostic code is no longer active when the fuse is removed. The switch has failed.Repair: Install the fuse in the fuse holder. Check the continuity of the switch in each position. Replace the switch. Verify that the new switch has corrected the problem.STOP
NOT OK - The CID 0722 FMI 03 diagnostic code remains active when the fuse is removed. The switch is not causing the problem.Repair: Install the fuse in the fuse holder before proceeding to the next Test Step.Proceed to Test Step 2.Test Step 2. CHECK THE ENERGIZE CIRCUIT OF THE SOLENOID FOR A SHORT
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the solenoid from the harness connector.
Disconnect the J1 and J2 machine harness connectors from the ECM.
With the service brake released, measure the resistance from contact J2-5 wire (G731-GY(Grey)) to all other contacts in the connectors.Expected Result:Each resistance measurement is greater than 5000