General System Description

PURPOSE
The Electronically Controlled Multipoint Injection system (ECI-MULTI)maintains emission levels and fuel economy within government agency standards, while optimizing driveability. The system consists of an engine control module (ECM), control relay, wiring, sensors and actuators.

OPERATION
The ECM uses an 8-bit microprocessor, Random Access Memory (RAM), Read Only Memory (ROM) and an Input/Output (I/0) interface. The control relay supplies positive current to the purge solenoid, ECM, and injectors.

The system also performs self-diagnostic procedures and provides back-up functions if certain circuits fail.


SENSORS/INPUTS
- A/C control units
- Air flow sensor (AFS)
- Anti-lock brake signal
- Barometric pressure sensor
- Battery voltage
- Crankshaft Position sensor
- Detonation "knock" sensor
- Electrical load switch
- Engine coolant temperature sensor
- Engine coolant temperature switch (A/C)
- Idle position switch
- Ignition switch
- Ignition timing adjustment connector
- Inhibitor switch (A/T only)
- Intake air temperature sensor
- Muffler mode change over switch
- 4 Oxygen sensors
- Power steering load switch
- Transaxle control module (A/T only)
- Throttle position sensor
- Vehicle speed sensor
- Camshaft Position sensor

ACTUATORS/OUTPUTS [1]
1 Fuel Injector
2 EGR Solenoid
3 EVAP Purge Control Solenoid
4 AC Motor
5 Fuel Pressure Solenoid
6 Turbocharger Wastegate Control Solenoid
7 A/C Compressor Clutch Relay
8 Fuel Pump Relay
9 Ignition Coil
10 Malfunction Indicator Light

[1] The numbers correspond to the output lines from the ECM in the accompanying illustration.