Pgm-Fi System; Alternator Control; Barometric Pressure (Baro) Sensor; Engine Coolant Temperature (Ect) Sensor - Honda S2000 Service Manual

Fuel and Emissions Systems
System Descriptions (conf d)
PGM-FI System
The Programmed Fuel Injection (PGM-Fl) system is a
sequential multiport fuel injection system.
Alternator Control
The alternator signals the ECM during charging. The
ECM then controls the voltage generated at the
alternator according to the electrical load determined
by the ELD (Electrical Load Detector) and driving mode.
This reduces engine load to improve fuel economy.
A/C Switch
The Ay'C (air conditioning) switch signals the ECM
whenever there is a demand for coolino.
A/C Compressor Clutch Relay
When the ECM receives a demand for cooling from the
Ay'C system, it delays the compressor from being
energized, and enriches the mixture to assure smooth
transition to the Iy'C mode.
Barometric Pressure {BARO) Sensor
The BARO sensor is inside the ECM. lt converts
atmospheric pressure into a voltage signalthat
modifies the basic duration of the fuel iniection
discharge.
Crankshaft Position (CKP) Sensor
The CKP sensor determines timing for injection of each
cylinder and also detects engine speed.
The ECM detects misfiring by using the CKP sensor to
monitor fluctuations in crankshaft sDeed. lt will then set
DTCs depending on how much misfiring occurs.
11-22
Engine Coolant Temperature (ECT) Sensor
The ECT sensor is a temperature dependent resistor
(thermistor). The resistance of the thermistor decreases
as the engine coolant temperature increases.
Intake Air Temperature llATl Sensor
The IAT sensor is a temperature dependent resistor
(thermistor). The resistance of the thermistor decreases
as the intake air temDerature increases.
THERMISTOR
THERMISTOR