DISC 0546480 - Caterpillar

System Operation Description:The engines Electronic Control Module (ECM) has the ability to crank the engine when the Engine Control Switch (ECS) is placed in the START position. The engine control will start the first crank cycle, when the ECS is placed in the START position. The crank cycle will continue for the time that is equal to the cycle crank time that has been programmed or the crank cycle will continue until the engine speed reaches the crank terminate speed. If crank terminate speed is not reached before the crank cycle time, the starting motor will deactivate at the end of the crank cycle time.This process will repeat for a programmed amount of times (Total Number of Crank Cycles). If the engine does not start, the Caterpillar Electronic Technician (ET) will display "OVERCRANK". The engine control will be in an idle state. The process can be restarted by turning the ECS to the OFF/RESET. Next turn the ECS to the STOP position. Then turn the ECS to the START position.The Manual Crank Start switch is located in the instrument panel. The manual crank start switch can be used to crank the engine for troubleshooting purposes. The manual crank start switch will override any other engine controls and/or protective devices. The manual crank start switch can be used to activate the starting motors. The manual crank start switch can be used to start the engine when the secondary ECM is in control of the engine. DO NOT use the manual crank start switch for normal engine operation.
Illustration 1 g00809892
Note: The Engine Control Switch (ECS) is mounted within an instrument panel that is located on the right side of the engine. The ECS is locked into the AUTO position with a pin. The pin must be removed in order to perform this test. After performing this test, ensure that the ECS is placed in the AUTO position and that the locking pin has been reinstalled.Test Step 1. Check for Connector Damage.
Disconnect the main power.
Thoroughly inspect the ECM connectors J1/P1 and J2/P2. Inspect all of the other connectors. Refer to the diagnostic functional test Troubleshooting, "Inspecting Electrical Connectors" for details.
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the circuit.
Check the ECM connector (allen head screw) for the proper torque of 6.0 N m (55 lb in).
Check the customer connector (allen head screw) for the proper torque of 2.25 0.25 N m (20 2 lb in).
Check the harness and the wiring for abrasion and pinch points.Expected Result:All connectors, pins, and sockets are coupled and/or inserted, and the harness and wiring should be free of corrosion, of abrasion or of pinch points.Results:
OK - The connectors and wiring are okay. Proceed to test step 2.
Not OK - The connectors and/or wiring need repair.Repair: Repair the connectors or wiring and/or replace the connectors or wiring.STOPTest Step 2. Attempt to Start the Engine
Turn the circuit breaker for the battery to the ON