ENGINE AR-PRIMARY 4858027 - Caterpillar

Illustration 1 g01297355
Connections for the boom down solenoidThis diagnostic code is associated with the solenoid valve. The "Output low" means that the module has determined that an open in the circuit exists. The possible causes of this diagnostic code are listed below:
The energize circuit of the solenoid is open.
The return circuit of the solenoid is open.
The solenoid has failed.
The module has failed. This is unlikely. 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. Ensure that the diagnostic code of "Output low" for pin 31 of the IQAN-XP2 A0 module is active before performing this procedure.Note: Use a Digital Multimeter for the measurements in this procedure.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 active diagnostic code from the machine harness.
At the machine harness connector for the solenoid, place a jumper wire from contact 1 (wire K952-BR) to contact 2 (wire K950-GN).
Observe the status of the "Output low" diagnostic code.Expected Result:The diagnostic code is active. Then, the diagnostic code changes from "Output low" to "Output high" as the jumper wire is installed.Results:
YES - The diagnostic code remains active. The jumper wire does not affect the diagnostic code. Proceed to Test Step 2.
NO - The diagnostic is no longer active. The solenoid has failed.Repair: The solenoid has failed. Replace the solenoid. Verify that the new solenoid corrects the problem.STOPTest Step 2. CHECK THE HARNESS FOR AN OPEN.
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the machine harness connector(s) from the module.
The jumper wire that was installed in the previous Test Step remains in place.
At the machine harness connector, measure the resistance from signal contact IQAN XP2 A0 - 31 (wire K950-GN) to contact IQAN XP2 A0 - 32 (wire K952-BR).Expected Result:The resistance is 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 5000 ohms. The resistance measurement is not correct. There is an open circuit in the machine harness.Repair: 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 and check the wires for damage to the insulation that is caused by excessive heat, battery acid, or chafing.
Perform a 45 N (10 lb) pull test on each of the wires that are associated with the circuit.
Reconnect all harness connectors making sure that the connectors are fully seated and the clips for each connector are completely fastened.
Turn the disconnect switch and the key start switch to the ON position.
Operate the machine.
Check the status of the "Output low" diagnostic code for pin 31 of the IQAN-XP2 A0 module.Expected Result:The "Output low" diagnostic code for pin 31 of the IQAN-XP2 A0 module is