COUPLING & GUARD GP 8G4678 - Caterpillar

Illustration 1 g00683014
This illustration represents the schematic for the "PTO Engine RPM Set Speed Input A" switch circuit.
Illustration 2 g00683021
This illustration represents the schematic for the "PTO Engine RPM Set Speed Input B" switch circuit.
Illustration 3 g00683028
Terminal Locations for ECMTest Step 1. Check the Electrical Connectors and the Wiring
Thoroughly inspect the ECM vehicle harness connector J1/P1, the connectors, and the firewall bulkhead connectors. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the suspect switch circuit.
Check the ECM connector (allen head screw) for the proper torque of 6.0 N m (55 lb in).
Check the harness and the wiring for abrasion and pinch points from the battery to the ECM. Then, check from the ignition key switch to the ECM.Refer to Illustration 3 for terminal locations for the ECM.Expected Result:All connectors, pins, and sockets are completely coupled and/or inserted, and the harness and wiring should be free of corrosion, abrasion or pinch points.Results:
OK - Proceed to Test Step 2.
Not OK - Repair: Repair the wiring and connectors or replace the wiring or the connectors. Ensure that all of the seals are properly connected.Verify that the repair eliminates the problem.STOPTest Step 2. Check the Status of the "PTO Engine RPM Set Speed Input A" and "PTO Engine RPM Set Speed Input B" on ET
Connect the Caterpillar Electronic Technician (ET) to the cab data link connector.
Turn the ignition key switch to the ON position.
Operate the switch in the ON and OFF positions.
View the switch status on ET.
If the "PTO Engine RPM Set Speed Input A" status indicates "Not Installed", then the parameter has not been programmed. If the "PTO Engine RPM Set Speed Input B" status indicates "Not Installed", then the parameter has not been programmed.Expected Result:The status screen should indicate "ON" if the switch is turned on. The status screen should indicate "OFF" if the switch is off.Results:
OK - The switch is operating normally. Continue troubleshooting if the original condition is not resolved.STOP
Not OK -