Chrysler 1997 Stratus Convertible RHD Service Manual page 891

JX
DESCRIPTION AND OPERATION (Continued)
IDLE AIR CONTROL MOTOR—PCM OUTPUT
The Idle Air Control (IAC) motor is mounted on the
throttle body. The PCM operates the idle air control
motor (Fig. 25) or (Fig. 26). The PCM adjusts engine
idle speed through the idle air control motor to com-
pensate for engine load, coolant temperature or baro-
metric pressure changes.
The throttle body has an air bypass passage that
provides air for the engine during closed throttle idle.
The idle air control motor pintle protrudes into the
air bypass passage and regulates air flow through it.
The PCM adjusts engine idle speed by moving the
IAC motor pintle in and out of the bypass passage.
The adjustments are based on inputs the PCM
receives. The inputs are from the throttle position
sensor, crankshaft position sensor, coolant tempera-
ture sensor, MAP sensor, vehicle speed sensor and
various switch operations (brake, park/neutral, air
conditioning).
Fig. 25 Idle Air Control Motor Air Bypass Passage—
2.4L
HOOD RELEASE THROTTLE POSITION SEN- SOR
Fig. 26 Idle Air Control Motor Air Bypass Passage—
DATA LINK CONNECTOR
The data link connector (diagnostic connector)
links the DRB scan tool with the Powertrain Control
Module (PCM). Refer to On-Board Diagnostics in
Group 25 - Emission Control Systems. The data link
connector is located inside the vehicle, under the
instrument panel, at the driver's kick panel (Fig. 27).
Fig. 27 Data Link (Diagnostic) Connector
FUEL INJECTORS—PCM OUTPUT
All engines use electrically operated top feed fuel
injectors (Fig. 28). The Automatic Shutdown (ASD)
relay supplies battery voltage to the fuel injectors. The
PCM controls the ground path for each injector in
sequence. By switching the ground paths on and off, the
PCM fine-tunes injector pulse width. Injector pulse
width refers to the amount of time an injector operates.
The PCM determines injector synchronization from
the camshaft position sensor and crankshaft position
sensor inputs. The PCM grounds the ASD and fuel
pump relays after receiving the camshaft position
sensor and crankshaft position sensor inputs.
DIAGNOSTIC DRIVER'S THROTTLEBODY IDLE KICK PANEL AIR NECTOR SIDE CON- CONTROL
FUEL SYSTEM 14 - 37
2.5L
MOTOR