BOLT 1073786 - Caterpillar

Illustration 1 g01457123
There are two terminal boxes on the G3520B engine. (1) Terminal box for the master ECM (2) Terminal box for the slave ECM
Illustration 2 g01089866
ECM in a terminal box for industrial applicationThe master Electronic Control Module (ECM) controls most of the engine's functions. The module is an environmentally sealed unit that is in an engine mounted terminal box. The ECM monitors various inputs from sensors in order to activate relays, solenoids, etc at the appropriate levels. The master ECM supports the following primary functions:
Start/stop control
Control of ignition for the left bank
Governing of the engine
Air/fuel ratio control
Monitoring of the detonation sensors on the left bank
Monitoring of the electrical system
Monitoring of engine operationThe slave ECM supports the following functions:
Control of ignition for the right bank
Monitoring of the detonation sensors on the right bankNeither ECM has a removable personality module. The software is changed by the flash programming of a file via the Caterpillar Electronic Technician (ET).