Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Computers and Control Systems: Description and Operation

ECU System:





Based on the information from the input sensors, the ECU determines the optimum control for the operating conditions and drives the output actuators accordingly. The ECU consists of an 8-bit microprocessor, random access memory (RAM), read only memory (ROM) and Input/Output (I/0) interface. The ECU actively controls the operation of the Fuel Injection system, the Ignition timing, and has full control of the Idle Speed Control system. Additionally the ECU interrupts the operation of the Air Conditioning and EGR systems under some conditions, and controls the power to the Fuel Pump. Each of these systems is covered in detail in COMPONENT OPERATION along with the input sensors used to supply the operating conditions to the ECU.