Pgm-Fi System - Honda 2002 Accord Manual

Fuel and Emissions Systems
System Descriptions (cont'd)
PGIVt-Ft System
The P r o g r a m m e d Fuel Injection (PGM-FI) system is a
sequential m u l t i p o r t fuel injection system.
Air conditioning (A/C) Switch
The A/C (air conditioning) switch signals the ECM/PCM
w h e n e v e r there is a demand for cooling.
A / C Compressor Clutch Relay
W h e n the ECM/PCM receives a d e m a n d for cooling
f r o m the A/C system, it delays the compressor f r o m
being energized, and enriches the mixture t o assure
s m o o t h transition to the A/C m o d e .
Air Fuel Ratio {A/F) Sensor (F23A4 engine)
The A/F Sensor operates over a w i d e air/fuel range. The
A/F Sensor is installed in the exhaust m a n i f o l d .
Z I R C O N I A
E L E M E N T
S E N S O R
T E R M I N A L S
0 0
H E A T E R
T E R M I N A L S
H E A T E R
Alternator Control
The alternator signals the ECM/PCM during charging.
The ECM/PCM then controls the voltage generated at
the alternator according to the electrical load
determined by the ELD (Electrical Load Detector) and
driving m o d e . This reduces engine load to i m p r o v e fuel
economy.
Barometric Pressure (BARO) Sensor
The barometric pressure sensor is inside the ECM/PCM.
It converts atmospheric pressure into a voltage signal
that modifies the basic duration of the fuel injection
discharge.
Crankshaft Position (CKP) and Top Dead Center (TDC)
Sensors
The CKP sensor determines fuel injection t i m i n g and
ignition t i m i n g for each cylinder, and also detects
engine speed. The TDC sensor determines ignition
t i m i n g at start-up and when crankshaft position signal
is abnormal.
C K P S E N S O R
T D C S E N S O R
Cylinder Position (CYP) Sensor
The CYP sensor inside the distributor detects the
position of the No. 1 cylinder as a reference for
sequential fuel injection to each cylinder.
F23A1, F23A4 engine:
F23A5 engine:
CYP ROTOR
11-24