HOUSING 4N0934 - Caterpillar

Illustration 1 g02153156
Schematic of the Flow Limit Pressure solenoid
This diagnostic code is associated with the Flow Limit Pressure solenoid. An FMI 05 diagnostic code means the ECM has determined the current of the solenoid circuit is below normal. Possible causes of this diagnostic code are listed below:
The Flow Limit Pressure solenoid has failed.
An open wire in the Flow Limit Pressure solenoid circuits.
The Machine ECM may have failed (unlikely).Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes now, but clear those codes after the original diagnostic code has been corrected.Note: Poor connections are often the cause of a problem in electrical circuits. Before performing this procedure, inspect all of the harness connectors involved in the circuit. Verify that all of the connections in the circuit are clean, secure, and in good condition. If a problem is found with any of the connections: correct the problem and verify that diagnostic code CID 1590 FMI 05 is still active, before performing the following procedures. System Response:When this diagnostic code is active, the ECM will turn off the current to the failed solenoid.Test Step 1. CHECK THE SOLENOID, THE ECM, AND THE CIRCUIT CONNECTIONS IN THE MACHINE HARNESS.
Turn the disconnect switch and the key start switch to the OFF position.
Disconnect the machine harness connector from the Flow Limit Pressure solenoid.
At the harness connector for the solenoid, place a jumper wire from contact 1 (M737-WH(White)) to contact 2 (M739-YL(Yellow)) on the connector.
Turn the disconnect switch and the key start switch to the ON position. Do not start the engine.
Observe the status of the CID 1590 FMI 05 diagnostic code. Expected Result:The CID 1590 FMI 05 diagnostic code remains active. Results:
YES - The CID 1590 FMI 05 code remains active. The jumper wire did not change the code. The solenoid is NOT the cause of the problem.Repair: The machine harness has failed, or the ECM may have failed.Go to Test Step 2.
NO - The CID 1590 FMI 05 code is NOT active, and has been replaced by an active CID 1590 FMI 06 diagnostic code. The ECM has detected a valid diagnostic code. Repair: The ECM, and the harness connections, are correct. The solenoid has failed. Perform Test Step 1 again, to verify the solenoid failure. Replace the solenoid. Go to Test Step 3.Test Step 2. CHECK THE MACHINE HARNESS FOR AN OPEN CONNECTION.
Turn the key start switch and the disconnect switch to the OFF position.
The jumper wire that was placed into the Flow Limit Pressure solenoid harness connector during Test Step 1 remains in place.
Disconnect the J2 machine harness connector from the machine ECM.
At the ECM J2 harness connector, measure the resistance from contact J2-9 (M737-WH(White)) to contact J2-35 (M739-YL(Yellow)) on the connector. Expected Result:The resistance is less than 5.0 ohms.Results:
YES - The resistance is less than 5.0 ohms. The machine harness is correct. Go to Test Step 3.
NO - The resistance is NOT less than 5.0 ohms. There is an open in the harness.Repair: The open is