CASE 3847491 - Caterpillar

Illustration 1 g02164390
Schematic of the Left Hopper Down SolenoidThis diagnostic code is associated with the Left Hopper Down Solenoid. The FMI 06 means that the LH Operator ECM has detected that the current for the solenoid circuit is above normal. Note: The LH Operator ECM is located under the LH Operator Platform.Conditions that could cause 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 situation is unlikely. System Response:When this diagnostic code is active, the following occurs:
Left hopper lower is disabled.
Operator station fault lamp is active.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, 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.Note: The resistance of the solenoid coil should be 27 1.4 ohms at 20 °C (68.0 °F).Test Step 1. CHECK THE SOLENOID
Turn the disconnect switch and the key start switch to the ON position. Do not start the engine.
Observe the status of the diagnostic code.
Disconnect the machine harness at the solenoid for the Hopper Lower hydraulic valve. Expected Result:The active CID 2552 FMI 06 diagnostic code changes to a CID 2552 FMI 05 diagnostic code when the solenoid is disconnected.Results:
YES - The active CID 2552 FMI 06 diagnostic code changes to a CID 2552 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. The resistance of the solenoid coil should be 27 1.4 ohms at 20 °C (68.0 °F). Replace the solenoid.STOP
NO - The CID 2552 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 signal contact J2-2 (wire A855-GY) to frame ground. Measure the resistance from the signal contact J2-2 (wire A855-GY) 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 resistance measurement is greater than