STRAINER 0994007 - Caterpillar

Illustration 1 g00803369
Schematic of the Proportional Solenoid Valve for Negative Flow ControlThis diagnostic code is associated with the proportional solenoid valve for negative flow control. This diagnostic code is recorded when the implement ECM reads the current of the solenoid as being below normal. There is an open circuit.The possible causes of this diagnostic code are listed:
The signal circuit of the solenoid is open.
The return circuit of the solenoid is open.
The solenoid has failed.
The implement ECM has failed. This is unlikely. System Response:When this diagnostic code occurs, there is no warning on the monitor. The diagnostic code will only be active when the control for the work tool is actuated. An example of this action is pressing the pedal for operating a hammer. The diagnostic code is active when the pedal is pressed. When the pedal is no longer pressed, the diagnostic code is not active, but the code is present in the diagnostic code log ("LOGGED ERROR" screen). 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 is 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.
Disconnect the solenoid with the diagnostic code from the machine harness.
At the machine harness connector for the solenoid, place a jumper wire from contact 1 (wire M737-WH) to wire (M739-YL).
Determine if CID 1524 FMI 05 is present. Check the "ACTIVE ERROR" screen on the monitor.Expected Result:The diagnostic code is not active when the jumper wire is installed. Results:
YES - The diagnostic code is not active when the jumper wire is installed. The circuit is correct. Repair: The solenoid has failed. Repeat this test step "CHECK THE SOLENOID" in order to verify the solenoid failure. Replace the solenoid. Verify that the new solenoid corrects the problem.STOP
NO - The diagnostic code remains active. The jumper wire does not affect the diagnostic code. Proceed to test step 2.Test Step 2. CHECK THE HARNESS FOR AN OPEN.
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the CONN171 and CONN172 machine harness connectors from the implement ECM.
At the machine harness connector for the solenoid, place a jumper wire from contact 1 (wire M737-WH) to contact 2 (wire M739-YL).
At the machine harness connector for the ECM, measure the resistance from signal contact CONN171-8 (wire M737-WH) to contact CONN171-28 (wire M739-YL) (return wire).Expected Result:The resistance should be less than 5.0 ohms.Results:
OK - The resistance is less than 5.0 ohms. The machine harness is correct. Proceed to test step 3.
NOT OK - The resistance is greater than 5.0 ohms. The resistance measurement is not correct. There is an open circuit in the machine harness.Repair: The open is in wire (M737-WH) or in wire (M739-YL) of the machine harness. Repair the machine harness or replace the machine harness.STOPTest Step 3. CHECK IF THE DIAGNOSTIC CODE REMAINS.
Inspect the harness connectors and clean the contacts of the harness connectors.
Reconnect