SWITCH GP-PRESSURE 1841564 - Caterpillar

The Electronic Modular Control Panel 3 (EMCP 3) controls the starting and stopping of the engine. The following inputs for the engine control are located on the panel for the EMCP 3: "RUN", "AUTO" and "STOP". The EMCP 3 has the ability to crank the engine directly via an internal relay. When the "RUN" switch is pushed on the panel an internal relay energizes the starting motor relays. Prior to cranking, the ECM will activate the prelube system. Refer to Troubleshooting, "Prelubrication System". The EMCP 3 will start the first crank cycle when the prelube is completed. The crank cycle continues for the programmed time or the engine speed reaches the crank terminate speed. If crank terminate speed is not reached before reaching the cycle crank time, the starting motor will deactivate for a time that is equal to the cycle crank time.This process will repeat for a programmed "Total Number of Crank Cycles". If the engine does not start, "ENGINE FAILURE TO START SHUTDOWN " will be displayed on the EMCP 3 in order to inform the operator of an overcrank condition. The engine control will be in an idle state. In order to restart the crank cycle, push the STOP switch and then push the RUN switch.Note: When the starting motor fails to engage the flywheel due to a butt engagement, that crank cycle will still be counted in the total number of crank cycles.
Illustration 1 g01190695
Typical schematic
Test Step 1. Inspect Electrical Connectors and Wiring
Turn the ECS to the OFF position. Turn the main disconnect switch to the OFF position.
Thoroughly inspect the J1/P1 ECM connector and the J2/P2 ECM connector. Inspect all of the connectors that are associated with the circuit. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connectors that are associated with the circuit.
Check the ECM connector (allen head screw) for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Check the harness and wiring for abrasion and for pinch points from the sensors back to the ECM. Expected Result:All connectors, pins and sockets are completely coupled and/or inserted and the harness and wiring are free of corrosion, of abrasion and of pinch points.Results:
OK - The harness and connectors appear to be OK. Proceed to Test Step 2.
Not OK - There is a problem with the connectors and/or wiring.Repair: Repair the connectors or wiring and/or replace the connectors or wiring. Ensure that all of the seals are properly in place and ensure that the connectors are completely coupled.Verify that the repair eliminates the problem.STOPTest Step 2. Attempt to Start the Engine
Connect Cat ET to the service tool connector J60/P60.
Turn the ECS to the STOP position. Turn the main disconnect switch to the ON position.
Observe the "startup mode" parameters on the Cat ET status screen.
Turn the engine control to the RUN or to the AUTO mode. Continue monitoring engine parameters as the engine cranks.
The crank cycle will continue