Dodge 2004 Neon SRT4, Diagnostic Manual

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the monitor run conditions, select the EGR PRE-
TEST in the DRB III
t
, OBD II Monitors Menu.
D. 02 SENSOR HEATER MONITOR
This monitor is now continuously running once
the heaters are energized. Pass information will be
processed at power down. For the monitor run
conditions, select the O2S HEATER MON PRE-
TEST in the DRB III
t
, OBD II Monitors Menu.
3.2.3 OTHER CONTROLS
CHARGING SYSTEM (NGC)
The charging system is turned on when the
engine is started. The Generator field is controlled
by the PCM using a 12-volt high-side driver and a
body ground circuit. The Generator output voltage
is determined by the PCM. When more system
voltage is needed, the PCM will applies a longer
duty cycle using the 12-volt high-side drive and
shortens duty cycle or none at all when less voltage
is needed.
O2 SENSOR (NGC)
The O2 system with ignition on and engine off
has a normalized O2 voltage of around 5 volts as
displayed on the DRBIII or measured with a high
impedance voltmeter. As the O2 sensor starts gen-
erating a signal the voltage will move towards 2.5
volts. The voltage will typically vary between 2.5
volts and 3.5 volts on a normal running engine. The
goal voltage is also typically between 2.5 and 3.5
volts. This implies that the 0-volt through 1-volt
range that you are used to is still valid, only it is
shifted up by a 2.5 volt offset. This 2.5 volt supply is
being delivered through the sensor return line.
SPEED CONTROL SYSTEM
The PCM controls vehicle speed by operation of
the speed control servo vacuum and vent solenoids.
Energizing the vacuum solenoid applies vacuum to
the servo to increase throttle position. Operation of
the vent solenoid slowly releases the vacuum allow-
ing throttle position to decrease. A special vacuum
dump solenoid allows immediate release of the
throttle during speed control operation.
Speed control may be cancelled by braking, driver
input using the speed control switches, shifting into
neutral, excessive engine speed (wheels spinning),
or turning the ignition off.
NOTE: If two speed control switches are
selected simultaneously, the PCM will detect
an illegal switch operation and turn the speed
control off.
TURBOCHARGER SYSTEM 2.4L (NCG)
The turbocharger is a performance part and must
not be tampered with. The wastegate bracket is an
integral part of the turbocharger. Tampering with
the wastegate components can reduce durability by
increasing cylinder pressure and thermal loading
due to incorrect inlet and exhaust manifold pres-
sure. Poor fuel economy and failure to meet regula-
tory emissions laws may also result. Increasing the
turbocharger boost WILL NOT increase engine
power. The turbocharger is an exhaust-driven su-
percharger, which increases the pressure and den-
sity of the air entering the engine. With the increase
of air entering the engine, more fuel can be injected
into the cylinders, which creates more power during
combusion. Refer to the Service Manual informa-
tion for description and operation of the Turbo
system. The Turbo system consists of the following
components.
• Turbocharger with Surge Valve and Wastegate
Actuators
• Surge Valve Solenoid
• Throttle Inlet Pressure (TIP) Solenoid
• Wastegate Solenoid
•
Throttle Inlet Pressure (TIP) Sensor
NATURAL VACUUM LEAK DETECTION (NVLD)
(NGC)
The Natural Vacuum Leak Detection (NVLD)
system is the next generation evaporative leak
detection system that will first be used on vehicles
equipped with the Next Generation Controller
(NGC) starting in 2002 M.Y. This new system
replaces the leak detection pump as the method of
5
GENERAL INFORMATION