DRIVE GP-SWING 1994539 - Caterpillar

Illustration 5 g00995689
Harness side of master ECM P1 connector (P1-52) Unswitched +battery (P1-63) -Battery
Insert two 7X-1710 Multimeter Probes into the harness side of the P1 connector. Insert the first probe into terminal 52. Insert the second probe into terminal 63. Connect a multimeter to the probes.
Switch the 16 amp circuit breaker ON.
Measure the power supply voltage at the P1 connector. During the measurement, wiggle the harness in order to check for an intermittent problem. Be sure to wiggle the harness near each of the connections. Record the measurement.
Switch the 16 amp circuit breaker OFF. Remove the probes from connector P1.
Illustration 6 g00903016
Harness side of the P3 connector for the slave ECM (P3-52) Unswitched +battery (P3-63) -Battery
Insert two 7X-1710 Multimeter Probes into the harness side of the P3 connector. Insert the first probe into terminal 52. Insert the second probe into terminal 63. Connect a multimeter to the probes.
Switch the 16 amp circuit breaker ON.
Measure the power supply voltage at the P3 connector. During the measurement, wiggle the harness in order to check for an intermittent problem. Be sure to wiggle the harness near each of the connections. Record the measurement.Expected Result:The voltage that is measured at the terminals for the power supply is at least 22 VDC. The voltage that is measured at the P1 connector and at the P3 connector is within 2 volts of the voltage that was measured at the terminals for the power supply. The voltage measurements are constant.Results:
OK - Each ECM is receiving the correct voltage.Repair: Perform the following procedure:Switch the 16 amp circuit breaker OFF.Remove the probes from connector P3. Proceed to Test Step 3.
Not OK - An ECM is not receiving the correct voltage.Repair: Perform the following procedure:
Switch the 16 amp circuit breaker OFF.
Remove the probes from connector P3.
Use a voltmeter to check the wiring. Refer to the schematic diagram for the electrical system. Locate the source of the voltage drop.
Make repairs, as needed.STOPTest Step 3. Check the Engine Control
Make sure that the engine will not crank during this procedure. For an engine with an electric starting motor, make sure that the battery cables are disconnected from the motor. For an engine with an air starting motor, make sure that the pressurized air supply is OFF. Make sure that the air is purged from the system.
Connect Cat ET to the service tool connector. Refer to Troubleshooting, "Electronic Service Tools".
Switch the 16 amp circuit breaker ON.Note: An "E225 Engine Overcrank" and/or an "E233 Low Engine Prelube Pressure" event code may be generated during this step. After you have completed this step, clear the events from the "Logged Events" screen of Cat ET.
Observe the "Active Diagnostic" screen on Cat ET and set the engine control to the STOP mode, the START