VALVE GP-SOLENOID & RELIEF 3237559 - Caterpillar

ON position.
Use the Cat ET service tool to determine the status of the Cat data-link. Expected Result:The Cat data-link is communicating with all the ECMs that are installed on the machine.Note: Some machines are equipped with only the MSS ECM.Results:
YES - The Cat data-link is communicating with all the ECMs that are installed on the machine. Proceed to Test Step 2.
NO - The Cat data-link is not communicating with all the ECMs that are installed on the machine. The Cat data-link has failed.Repair: Repair the Cat data-link circuits in the harness.STOPTest Step 2. CHECK THE SYSTEM VOLTAGE AT THE MSS ECM.
Measure the voltage between pin 1 and pin 3 of the MSS ECM.Expected Result:The voltage is approximately system voltage.Results:
YES - The voltage is approximately system voltage. Proceed to Test Step 3.
NO - The voltage is not approximately system voltage.Repair: Check the battery and the associated wiring in the machine harness. STOPTest Step 3. CHECK THE VOLTAGE FROM THE KEY SWITCH TO THE DRIVER (INPUT No. 1) OF THE ECM.
Turn the keyswitch to the ON position.
Measure the voltage between pin 9 and pin 3 if the wires are present. Record the reading.
Measure the voltage between pin 24 and pin 3 and record the reading.
Measure the voltage between pin 64 and pin 3 if the wires are present. Record the reading. Expected Result:Voltage should be present for all of the measurements. The voltage should