Electronic Control Unit

ECU
The electronic control unit(ECU) is the heart of the fuel injection system. It receives signals from various sensors and uses these signals to determine the amount of fuel needed at any given moment.
There are different operating paramaters for the fuel injection system for particular vehicles and because of this the ECU can not be interchanged between different models.
The ecu is a solid state device(no moving parts). When an ECU fails it is almost invariably because something outside that unit has failed, interfering with the signals into or out of the ECU. In this case, it is commom for the ECU to self-destruct, and since it is an expensive piece of equipment, it is advisable to exercise extreme caution when working with any components connected to the ECU. The two key precautions to take when working with the ECU connected components are: 1) never disconnect the ecu with the ignition switch in the ON position, and 2) always take extreme care with connectors to make sure that connecting pins enter only the correct receptacles.

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