ROD 0024924 - Caterpillar

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Brake Pressure Modulation Solenoid connections
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Location of the brake valve solenoidThis diagnostic code is associated with the Brake Pressure Modulation Solenoid. The solenoid is connected to a PWM driver output of the Machine ECM. The FMI 06 means that the ECM has detected the electrical current in the solenoid circuit is above normal.Under certain machine conditions, the Machine ECM will use the Brake Pressure Modulation Solenoid to proportionally apply the brakes in order to control the speed of the machine.Conditions that could causes this diagnostic code to be activated are:
The energize circuit of the solenoid is shorted to a ground source.
The solenoid has failed.
The ECM has failed. This is unlikely. Note: Poor connections can often be the cause of a problem in an electrical circuit. Verify that all connections in the circuit are clean, secure and 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: 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.Test Step 1. CHECK THE SOLENOID
Turn the disconnect switch and the key start switch to the ON position. DO NOT START THE ENGINE.
While observing the status of the active CID 2596 FMI 06 diagnostic code, disconnect the Brake Pressure Modulation Solenoid from the machine harness. Expected Result:The active CID 2596 FMI 06 diagnostic code changes to a CID 2596 FMI 05 diagnostic code when the solenoid is disconnected.Results:
YES - The active CID 2596 FMI 06 diagnostic code changes to a CID 2596 FMI 05 diagnostic code when the solenoid is disconnected. The solenoid circuit in the machine harness is correct.Repair: The solenoid has failed. Repeat this test "CHECK THE SOLENOID" in order to verify the solenoid failure. Replace the Brake Pressure Modulation Solenoid.After the solenoid is replaced, verify the new solenoid has corrected the problem before operating the machine.STOP
NO - The CID 2596 FMI 06 diagnostic code remains active. Disconnecting the solenoid did not change the status of the active diagnostic code. The solenoid is not causing the problem. Proceed to Test Step 2.Test Step 2. CHECK THE ENERGIZE CIRCUIT OF THE SOLENOID FOR A SHORT TO GROUNDThe solenoid remains disconnected from the machine harness.
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the machine harness ECM connectors J1 and J2 from the ECM.
At the machine harness ECM connectors, measure the resistance from the energize contact J1-52 (wire F792-WH) to frame ground. Measure the resistance from the signal contact J1-52 (wire F792-WH) to all of the other contacts that are used in J1 and J2 ECM connectors.
While observing the multimeter resistance measurements, wiggle the machine harness connectors for the ECM and the solenoid. Gently pull on the wires and move the wires around.Expected Result:Each