CONNECTOR-ORIFICE 7E9898 - Caterpillar

System Operation Description:The secondary Electronic Control Module (ECM) controls power to the secondary engine speed/timing sensor. The secondary ECM receives the input signals from the secondary engine speed/timing sensor and the primary engine speed/timing sensor. The secondary ECM also controls the air shutoff system by activating the output driver to the "ASOS" switch. The "ASOS" switch activates the air shutoff solenoids. The secondary ECM can also operate the fuel injector solenoids. This allows the secondary ECM to control fuel to the engine when the secondary ECM assumes control of the governing of the engine. All other engine functions are controlled by the primary ECM.When power is applied to the system, the secondary ECM will illuminate the "Secondary ECM Ready" lamp and the "Secondary ECM Active" lamp for five seconds. The "Secondary ECM Ready" lamp should stay illuminated.The secondary ECM provides governing of the engine if the primary ECM fails. If this occurs, the secondary ECM automatically assumes engine control. When the secondary ECM assumes engine control, the "Secondary ECM Active" lamp will illuminate.The secondary ECM will take control due to the following reasons:
Loss of the primary ECM heartbeat signal
Two injector faults for the eight or the twelve cylinder engine
Four injector faults for the sixteen cylinder engineNote: The secondary ECM will remain in control of the engine until the power is cycled. The secondary ECM is not a fully functional ECM. The secondary ECM is used to keep the engine running until the vessel can obtain proper service.
Illustration 1 g01029811
Typical exampleTest Step 1. Check for Connector Damage.
Turn the ECS to the OFF/RESET position.
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 1 N m (53 9 lb in).
Check the harness and the wiring for abrasion and for pinch points.Expected Result:All connectors, pins, and sockets are completely coupled and/or inserted, and the harness and wiring are 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. Check the "Secondary ECM Active" Lamp and the "Secondary ECM Ready" Lamp.
Observe the "Secondary ECM Active" lamp and the "Secondary ECM Ready" lamp on the instrument panel when the ECS is turned to the STOP position.Expected Result:Both lamps illuminate for five seconds. The "Secondary ECM Ready" lamp stays illuminated. The "Secondary ECM Active" lamp turns off after five seconds.Results:
OK - Both lamps illuminated for five seconds. The "Secondary ECM Ready" lamp remained illuminated. The "Secondary ECM Active" lamp is off. The problem is no longer present.Repair: The secondary ECM reads the primary ECM heartbeat signal. Active injector