VALVE AS-ELECTRIC 1145905 - Caterpillar

Illustration 1 g01247836
Schematic of the Boom Overload Pressure SensorThis diagnostic code is recorded when the ECM reads the signal voltage of the pressure sensor as being too high.The possible causes of this diagnostic code are listed:
The sensor has failed.
The sensor supply or the ground circuit in the machine harness is open.
The signal circuit in the machine harness is open or the sensor is disconnected.
The machine ECM has failed. This is unlikely.Test Step 1. CHECK THE SENSOR.
Turn the disconnect switch and the key start switch to the ON position.
Ensure that the diagnostic code is present.
Observe the status of the diagnostic code. Then, disconnect the machine harness from the sensor.Expected Result:If the sensor is not the cause of the diagnostic code, the diagnostic code remains present. If the sensor has failed, the diagnostic code is NO longer present.Results:
OK - The diagnostic code remains present. The sensor has not failed. The machine harness or the ECM may have failed. Proceed to test step 2.
NOT OK - The diagnostic code is NO longer present. The machine harness is correct and the ECM is operating properly. The sensor has failed.Repair: Replace the sensor. Verify that the new sensor corrects the problem.STOPTest Step 2. CHECK THE SIGNAL CIRCUIT.
Turn the key start switch and the disconnect switch to the OFF position.
The machine harness remains disconnected from the sensor.
Disconnect the J1 and J2 connector from the ECM.
At the J1 connector for the ECM, measure the resistance from contact J1-37 (wire H446-PK) to all other J1 and J2 contacts.Expected Result:The resistance should be greater than 5 ohms.Results:
YES - The resistance is greater than 5 ohms. The harness is correct. Proceed to test step 3.
NO - The resistance is not greater than 5 ohms for each measurement. There is a short in the harness.Repair: The short is in the wire with the low resistance measurement. Repair the harness or replace the harness.STOPTest Step 3. CHECK THE RETURN CIRCUIT FOR AN OPEN.
The sensor remains disconnected.
The disconnect switch and the key start switch remain in the OFF position.
The machine harness connectors remain disconnected from the ECM.
At the J1 connector for the ECM, measure the resistance between the return contact J1-18 (wire A209-BK) and contact 2 (wire A209-BK) at the sensor. Expected Result:The resistance is less than 5 ohms.Results:
YES - The resistance is less than 5 ohms. The harness resistance is correct. Proceed to test step 4.
NO - The resistance is greater than 5 ohms. The return circuit of the harness has failed.Repair: There is an open in the return wire (A209-BK). Repair the machine harness or replace the machine harness.STOPTest Step 4. CHECK IF THE DIAGNOSTIC CODE REMAINS.
Inspect the contacts and clean the contacts of the harness connectors.
Reconnect all harness connectors.
Turn the disconnect switch and the key start switch to the ON position.
Operate the machine.
Check if the diagnostic code is active.Expected Result:The diagnostic code is NOT active.Results:
YES - The diagnostic code is NO longer active. The initial diagnostic code was probably caused by a poor electrical connection or a short at