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| Illustration 1 | g02720497 |
Connections of the Service Brake Dump solenoid | |
A CID 0722 is associated with the Service Brake Dump solenoid. An FMI 06 means the machine ECM has determined the current in the solenoid circuit is above normal.
Possible causes of this diagnostic code are:
- Service Brake Dump solenoid failure.
- Service Brake Dump solenoid circuit ground.
- Machine ECM failure, but is most unlikely.
Note: Poor connections often cause problems in electrical circuits. Before performing this procedure, inspect all the machine harnesses and connectors involved in the circuit. Make sure to verify that all of the connections in the circuit are clean, secure, and in good condition. Correct any problems found with any of the connections. Verify the diagnostic code CID 0722 FMI 06 is still active, before continuing with this procedure.
Note: The following test procedure may create other diagnostic codes. Ignore all the created diagnostic codes now, but clear all those codes after the cause for the original diagnostic code has been corrected.
Test Step 1. CHECK THE SOLENOID AND ECM.
- Turn the disconnect switch, and the key start switch, to the OFF position.
- Disconnect the harness connector from the Service Brake Dump solenoid .
- Turn the disconnect switch, and the key start switch, to the ON position.
- Observe the status of the CID 0722 FMI 06 diagnostic code.
Expected Result:
The diagnostic code does not change and remains active.
Results:
- YES - The diagnostic code does not change and remains active. The solenoid is not the problem. Go to Test Step 2.
- NO - The diagnostic code is no longer active, and has changed into an active CID 0722 FMI 05 diagnostic code. The solenoid has failed.
Repair: Replace the solenoid.
Go to Test Step 3.
Test Step 2. CHECK THE SOLENOID CIRCUITS FOR A GROUND SHORT.
- Turn the disconnect switch, and the key start switch, to the OFF position.
- The Service Brake Dump solenoid remains disconnected from the harness connector.
- Disconnect the harness connector from the Service Brake pedal switch.
- Disconnect the J2 harness connector from the machine ECM.
- At the J2 ECM harness connector, measure resistance from contact J2-5 (wire G731-GY) to all other contacts used in the J2 ECM harness connector.
Expected Result:
Each resistance is more than 5000 ohms.
Results:
- YES - Each resistance is more than 5000 ohms. There are no short circuits in the harness. Go to Test Step 3.
- NO - A resistance is less than 5000 ohms. There is a short circuit in the harness.
Repair: The short is from contact J2-5 wire G731-GY) to the circuit with the low resistance measurement. Repair or replace the harness.
Go to Test Step 3.
Test Step 3. CHECK THE DIAGNOSTIC CODE STATUS.
- Inspect and clean all contacts in the harness connectors. Reconnect all harnesses. Make sure all the connectors are securely tightened.
- Turn the disconnect switch and the key start switch to the ON position.
- Clear all inactive diagnostic codes.
- Operate the machine.
- Observe the status of the CID 0722 FMI 06 diagnostic code.
Expected Result:
The diagnostic code is no longer active.
Results:
- YES - The diagnostic code is no longer active, and does not exist at this time. The problem has been corrected.
Repair: Return machine to normal operation
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- NO - The diagnostic code is still active. The cause for the problem has not been corrected.
Repair: If you have not inspected the harness connectors in a previous Test Step, do that now. Clean the contacts of the harness connectors. Check the wires for damage to the insulation caused by excessive heat, battery acid, or chafing.Perform a 45 N (10 lb.) pull test on each of the wires that are associated with the sensor circuit.Perform a "wiggle test" on the sensor circuit of the machine wiring harness, using the Caterpillar Electronic Technician service tool. The "wiggle test" can be used to detect open or shorted connections in the machine wiring harness.Reconnect all harness connectors. Make sure that the connectors are fully seated. Observe that the clips for each connector are securely fastened. Perform Test Step 3 again. If the problem has NOT been found, and the original code is still active, the machine ECM may have failed.Prior to replacing an ECM, always contact your Dealership Technical Communicator for possible consultation with Caterpillar, or with the Dealer Solutions Network. This consultation may greatly reduce repair time. If the ECM needs to be replaced, see Testing and Adjusting, "Electronic Control Module (ECM) - Replace".
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