PLUNGER 9S8569 - Caterpillar

Troubleshooting Procedure for Solenoid
The solenoid is used to shutoff, release, distribute, or mix fluids on the machine. Generally, multiple solenoids are located together on a manifold. The solenoid converts electrical energy into magnetic energy, moving a spool located inside the housing of the valve. A spring is used to hold the spool in position until the solenoid is energized.The magnetic force that acts on the valve spool is created when a coil inside the solenoid is energized.Possible Causes for an FMI 3 Diagnostic code are:
The harness is shorted.
The ECM has failed. A failure of the ECM is unlikely.Possible causes for an FMI 5 Diagnostic code are:
There is an open in the circuit.
The solenoid has failed.
The ECM has failed. A failure of the ECM is unlikely.Possible causes for an FMI 6 Diagnostic code are:
A wire is shorted to ground.
The solenoid has failed.
The ECM has failed. A failure of the ECM is unlikely.
Table 3
Troubleshooting Test Steps Values Results
1. Identify Active FMI Code Associated With Solenoid Circuit
Code present. FMI 3 diagnostic code, proceed to Test Step 2.
FMI 5 diagnostic code, proceed to Test Step 3.
FMI 6 diagnostic code, proceed to Test Step 5.
Begin Process For FMI 3 Troubleshooting HERE
2. Check The Machine Harness For A Short
A. Turn the key start switch and the disconnect switch OFF.
B. Disconnect the harness connection at solenoid.
C. If the solenoid is connected to ECM, disconnect J1 and J2 connectors from ECM. If the solenoid is connected to the switch panel, disconnect all switch panel connectors.
D. Measure the resistance of solenoid signal contact to all J1 and J2 connectors.
Each reading is greater than 5K Ω. OK - All resistance readings are greater than 5K Ω .
Proceed to Test Step 7.
NOT OK - One or more readings are less than 5 Ω.
Repair - A short exists between the signal contact and the circuit with the low resistance. Repair or replace the machine harness.
Note: A resistance that is greater than 5 Ω but less than 5K Ω would indicate a loose connection or a corroded connection in the circuit. A resistance measurement that is greater than 5K Ω would indicate an open in the circuit.
STOP
Begin Process For FMI 5 Troubleshooting HERE
3. Check The Solenoid.
A. Turn the key start switch and the disconnect switch OFF.
B. Disconnect the solenoid from the machine harness.
C. Place a jumper wire between contact 1 and contact 2, at the harness connector for the solenoid.
D. Turn the key start switch and the disconnect switch ON. Do not start the engine.
E. As the jumper is removed and connected to the contacts, observe any code change.
The code changes to FMI 6 after the jumper wire is installed. OK - The circuit is correct, the solenoid has failed.
Repair: Replace the solenoid.
After replacement of the solenoid, confirm the diagnostic code is not active.
STOP
NOT OK - The diagnostic code remains active.
Proceed to Test Step 4.
4. Check The Machine Harness For An Open.
A. Turn the key start switch and the disconnect switch OFF.
B. Disconnect the harness connectors from the ECM (or switch