2001 CHRYSLER VOYAGER Memory switch input open

NOTE: The VTSS will not arm by pushing down the
door lock mechanism. This will manually override
the system.
For Door Cylinder Lock Switch Removal and
Installation, refer to Electrical, Power Locks, Door
Cylinder Lock Switch.
If the VTSS is triggered, the horn will pulse, head-
lamps/marker lamps will flash, and the VTSS warn-
ing lamp will flash. If BCM determines the threat to
be false and the VTSS is not triggered again, the sys-
tem will shut down and rearm itself after three min-
utes. If a trigger is still active, the alarm will
continue for an additional 15 minutes without the
horn. The VTSS monitoring portion of the system is
split into two sections. The engine compartment sec-
tion and the passenger compartment section. If a
malfunction occurs in the engine compartment sec-
tion, the passenger compartment section would still
arm and function normally.
NOTE: If hood is not secure during the arming
sequence, the lamp will stay lit and not flash. The
system will arm with hood not secured (hood ajar
switch closed) and the liftgate open (liftgate ajar
switch closed). System will not arm if passenger
compartment is not secure (all switches closed)
ARMING THE VTSS - METHOD A
(1) With the key removed from the ignition lock
and any door open (excluding liftgate), actuate one of
the following:
²Power door lock button to LOCK,
²Key fob LOCK button
²Door lock key cylinder to locked position.
(2) Close all opened doors. Liftgate can remain
open.
(3) After the last door is closed, an arming time-
out period of sixteen seconds will start, then the
VTSS will become armed.
ARMING THE VTSS - METHOD B
Actuating the key fob transmitter LOCK button,
key locking the front doors or liftgate with the doors
closed and the ignition locked will begin the arming
time-out period. If method A, 16 second time-out
sequence was in process when method B was actu-
ated, the 16 second time-out will restart from the
time of the second actuation.
If the security lamp does not illuminate at all upon
final door closure, it indicates that the system is not
arming.
The current VTSS status armed or disarmed shall
be maintained in memory to prevent battery discon-
nects from disarming the system.
TRIGGERING THE VTSS
After the VTSS is armed, the following actions will
trigger the alarm:
²Opening any door.
²Opening the hood
²Turning the ignition to the ON, ACC, or
UNLOCK position.
²Opening liftgate without first receiving a RKE
input or liftgate key input.
CAUTION: The VTSS indicator LED will trigger and
engine will continue to run if the vehicle is
equipped with SKIS and the proper key is used to
start the vehicle. This condition will occur if the
VTSS has been triggered. If valid key is used, VTSS
will disarm
SENTRY KEY IMMOBILIZER SYSTEM
The SKIS includes keys from the factory which are
pre-programmed. Each SKIM will recognize a maxi-
mum of eight Sentry Keys. If the customer would
like to own additional keys other than those provided
with the vehicle, they can be purchased from any
authorized dealer. These keys must be programmed
to the SKIM on the vehicle in order for the system to
recognize them as valid keys. This can be done by
the dealer with a DRB IIItscan tool or by a cus-
tomer if this feature is available in their market and
they have two (2) valid keys already available to
them. Refer to the Service Procedures portion of this
system for additional details. The SKIS performs a
self-test each time the ignition switch is turned to
the ON position and will store Diagnostic Trouble
Codes (DTC's) if a system malfunction is detected.
The SKIS can be diagnosed and any stored DTC's
can be retrieved using a DRB IIItscan tool as
described in the appropriate Body Diagnostic Proce-
dures manual.
DIAGNOSIS AND TESTING - SENTRY KEY
IMMOBILIZER SYSTEM
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO ELECTRICAL, RESTRAINTS,
WARNINGS, BEFORE ATTEMPTING COMPONENT
DIAGNOSIS OR SERVICE. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
8Q - 2 VEHICLE THEFT SECURITYRS
VEHICLE THEFT SECURITY (Continued)

²The number of engine revolutions since cranking
was initiated
During Start-up the PCM maintains ignition tim-
ing at 9É BTDC.
ENGINE WARM-UP MODE
This is an OPEN LOOP mode. The following inputs
are received by the PCM:
²Engine coolant temperature
²Manifold Absolute Pressure (MAP)
²Inlet/Intake air temperature (IAT)
²Crankshaft position (engine speed)
²Camshaft position
²Knock sensor
²Throttle position
²A/C switch
²Battery voltage
²Vehicle speed
²Speed control
²O2 sensors
The PCM adjusts injector pulse width and controls
injector synchronization by turning the individual
ground paths to the injectors On and Off.
The PCM adjusts ignition timing and engine idle
speed. Engine idle speed is adjusted through the idle
air control motor.
CRUISE OR IDLE MODE
When the engine is at operating temperature this
is a CLOSED LOOP mode. During cruising or idle
the following inputs are received by the PCM:
²Inlet/Intake air temperature
²Engine coolant temperature
²Manifold absolute pressure
²Crankshaft position (engine speed)
²Camshaft position
²Knock sensor
²Throttle position
²Exhaust gas oxygen content
²A/C control positions
²Battery voltage
²Vehicle speed
The PCM adjusts injector pulse width and controls
injector synchronization by turning the individual
ground paths to the injectors On and Off.
The PCM adjusts engine idle speed and ignition
timing. The PCM adjusts the air/fuel ratio according
to the oxygen content in the exhaust gas (measured
by the upstream and downstream heated oxygen sen-
sor).
The PCM monitors for engine misfire. During
active misfire and depending on the severity, the
PCM either continuously illuminates or flashes the
malfunction indicator lamp (Check Engine light on
instrument panel). Also, the PCM stores an engine
misfire DTC in memory.The PCM performs several diagnostic routines.
They include:
²Oxygen sensor monitor
²Downstream heated oxygen sensor diagnostics
during open loop operation (except for shorted)
²Fuel system monitor
²EGR monitor
²Purge system monitor
²All inputs monitored for proper voltage range.
²All monitored components (refer to the Emission
section for On-Board Diagnostics).
The PCM compares the upstream and downstream
heated oxygen sensor inputs to measure catalytic
convertor efficiency. If the catalyst efficiency drops
below the minimum acceptable percentage, the PCM
stores a diagnostic trouble code in memory.
During certain idle conditions, the PCM may enter
a variable idle speed strategy. During variable idle
speed strategy the PCM adjusts engine speed based
on the following inputs.
²A/C sense
²Battery voltage
²Battery temperature
²Engine coolant temperature
²Engine run time
²Inlet/Intake air temperature
²Vehicle mileageACCELERATION MODE
This is a CLOSED LOOP mode. The PCM recog-
nizes an abrupt increase in Throttle Position sensor
output voltage or MAP sensor output voltage as a
demand for increased engine output and vehicle
acceleration. The PCM increases injector pulse width
in response to increased fuel demand.
DECELERATION MODE
This is a CLOSED LOOP mode. During decelera-
tion the following inputs are received by the PCM:
²A/C sense
²Battery voltage
²Inlet/Intake air temperature
²Engine coolant temperature
²Crankshaft position (engine speed)
²Exhaust gas oxygen content (upstream heated
oxygen sensor)
²Knock sensor
²Manifold absolute pressure
²Throttle position
²IAC motor control changes in response to MAP
sensor feedback
The PCM may receive a closed throttle input from
the Throttle Position Sensor (TPS) when it senses an
abrupt decrease in manifold pressure. This indicates
a hard deceleration. In response, the PCM may
14 - 18 FUEL INJECTIONRS
FUEL INJECTION (Continued)

momentarily turn off the injectors. This helps
improve fuel economy, emissions and engine braking.
WIDE-OPEN-THROTTLE MODE
This is an OPEN LOOP mode. During wide-open-
throttle operation, the following inputs are used by
the PCM:
²Inlet/Intake air temperature
²Engine coolant temperature
²Engine speed
²Knock sensor
²Manifold absolute pressure
²Throttle position
When the PCM senses a wide-open-throttle condi-
tion through the Throttle Position Sensor (TPS) it de-
energizes the A/C compressor clutch relay. This
disables the air conditioning system.
The PCM does not monitor the heated oxygen sen-
sor inputs during wide-open-throttle operation except
for downstream heated oxygen sensor and both
shorted diagnostics. The PCM adjusts injector pulse
width to supply a predetermined amount of addi-
tional fuel.
IGNITION SWITCH OFF MODE
When the operator turns the ignition switch to the
OFF position, the following occurs:
²All outputs are turned off, unless 02 Heater
Monitor test is being run. Refer to the Emission sec-
tion for On-Board Diagnostics.
²No inputs are monitored except for the heated
oxygen sensors. The PCM monitors the heating ele-
ments in the oxygen sensors and then shuts down.
FUEL CORRECTION or ADAPTIVE MEMORIES
DESCRIPTION
In Open Loop, the PCM changes pulse width with-
out feedback from the O2 Sensors. Once the engine
warms up to approximately 30 to 35É F, the PCM
goes into closed loopShort Term Correctionand
utilizes feedback from the O2 Sensors. Closed loop
Long Term Adaptive Memoryis maintained above
170É to 190É F unless the PCM senses wide open
throttle. At that time the PCM returns to Open Loop
operation.
OPERATION
Short Term
The first fuel correction program that begins func-
tioning is the short term fuel correction. This system
corrects fuel delivery in direct proportion to the read-
ings from the Upstream O2 Sensor.The PCM monitors the air/fuel ratio by using the
input voltage from the O2 Sensor. When the voltage
reaches its preset high or low limit, the PCM begins
to add or remove fuel until the sensor reaches its
switch point. The short term corrections then begin.
The PCM makes a series of quick changes in the
injector pulse-width until the O2 Sensor reaches its
opposite preset limit or switch point. The process
then repeats itself in the opposite direction.
Short term fuel correction will keep increasing or
decreasing injector pulse-width based upon the
upstream O2 Sensor input. The maximum range of
authority for short term memory is 25% (+/-) of base
pulse-width.
Long Term
The second fuel correction program is the long
term adaptive memory. In order to maintain correct
emission throughout all operating ranges of the
engine, a cell structure based on engine rpm and load
(MAP) is used.
Ther number of cells varies upon the driving con-
ditions. Two cells are used only during idle, based
upon TPS and Park/Neutral switch inputs. There
may be two other cells used for deceleration, based
on TPS, engine rpm, and vehicle speed. The other
twelve cells represent a manifold pressure and an
rpm range. Six of the cells are high rpm and the
other six are low rpm. Each of these cells is a specific
MAP voltage range .
As the engine enters one of these cells the PCM
looks at the amount of short term correction being
used. Because the goal is to keep short term at 0 (O2
Sensor switching at 0.5 volt), long term will update
in the same direction as short term correction was
moving to bring the short term back to 0. Once short
term is back at 0, this long term correction factor is
stored in memory.
The values stored in long term adaptive memory
are used for all operating conditions, including open
loop. However, the updating of the long term memory
occurs after the engine has exceeded approximately
17É F, with fuel control in closed loop and two min-
utes of engine run time. This is done to prevent any
transitional temperature or start-up compensations
from corrupting long term fuel correction.
Long term adaptive memory can change the pulse-
width by as much as 25%, which means it can correct
for all of short term. It is possible to have a problem
that would drive long term to 25% and short term to
another 25% for a total change of 50% away from
base pulse-width calculation.
RSFUEL INJECTION14-19
FUEL INJECTION (Continued)

put component, it can verify that the command was
carried out by monitoring specific input signals for
expected changes. For example, when the PCM com-
mands the Idle Air Control (IAC) Motor to a specific
position under certain operating conditions, it expects
to see a specific (target) idle speed (RPM). If it does
not, it stores a DTC.
PCM outputs monitored for functionality include:
²Fuel Injectors
²Ignition Coils
²Torque Converter Clutch Solenoid
²Idle Air Control
²Purge Solenoid
²EGR Solenoid
²LDP Solenoid
²Radiator Fan Control
²Trans Controls
OXYGEN SENSOR (O2S) MONITOR
DESCRIPTIONÐEffective control of exhaust
emissions is achieved by an oxygen feedback system.
The most important element of the feedback system
is the O2S. The O2S is located in the exhaust path.
Once it reaches operating temperature 300É to 350ÉC
(572É to 662ÉF), the sensor generates a voltage that
is inversely proportional to the amount of oxygen in
the exhaust. When there is a large amount of oxygen
in the exhaust caused by a lean condition, the sensor
produces a low voltage, below 450 mV. When the oxy-
gen content is lower, caused by a rich condition, the
sensor produces a higher voltage, above 450mV.
The information obtained by the sensor is used to
calculate the fuel injector pulse width. The PCM is
programmed to maintain the optimum air/fuel ratio.
At this mixture ratio, the catalyst works best to
remove hydrocarbons (HC), carbon monoxide (CO)
and nitrous oxide (NOx) from the exhaust.
The O2S is also the main sensing element for the
EGR, Catalyst and Fuel Monitors.
The O2S may fail in any or all of the following
manners:
²Slow response rate (Big Slope)
²Reduced output voltage (Half Cycle)
²Heater Performance
Slow Response Rate (Big Slope)ÐResponse rate
is the time required for the sensor to switch from
lean to rich signal output once it is exposed to a
richer than optimum A/F mixture or vice versa. As
the PCM adjusts the air/fuel ratio, the sensor must
be able to rapidly detect the change. As the sensor
ages, it could take longer to detect the changes in the
oxygen content of the exhaust gas. The rate of
change that an oxygen sensor experiences is called
'Big Slope'. The PCM checks the oxygen sensor volt-
age in increments of a few milliseconds.Reduced Output Voltage (Half Cycle)ÐThe
output voltage of the O2S ranges from 0 to 1 volt. A
good sensor can easily generate any output voltage in
this range as it is exposed to different concentrations
of oxygen. To detect a shift in the A/F mixture (lean
or rich), the output voltage has to change beyond a
threshold value. A malfunctioning sensor could have
difficulty changing beyond the threshold value. Each
time the voltage signal surpasses the threshold, a
counter is incremented by one. This is called the Half
Cycle Counter.
Heater PerformanceÐThe heater is tested by a
separate monitor. Refer to the Oxygen Sensor Heater
Monitor.
OPERATIONÐAs the Oxygen Sensor signal
switches, the PCM monitors the half cycle and big
slope signals from the oxygen sensor. If during the
test neither counter reaches a predetermined value, a
malfunction is entered and a Freeze Frame is stored.
Only one counter reaching its predetermined value is
needed for the monitor to pass.
The Oxygen Sensor Monitor is a two trip monitor
that is tested only once per trip. When the Oxygen
Sensor fails the test in two consecutive trips, the
MIL is illuminated and a DTC is set. The MIL is
extinguished when the Oxygen Sensor monitor
passes in three consecutive trips. The DTC is erased
from memory after 40 consecutive warm-up cycles
without test failure.
Enabling ConditionsÐThe following conditions
must typically be met for the PCM to run the oxygen
sensor monitor:
²Battery voltage
²Engine temperature
²Engine run time
²Engine run time at a predetermined speed
²Engine run time at a predetermined speed and
throttle opening
²Transmission in gear (automatic only)
²Fuel system in Closed Loop
²Long Term Adaptive (within parameters)
²Power Steering Switch in low PSI (no load)
²Engine at idle
²Fuel level above 15%
²Ambient air temperature
²Barometric pressure
²Engine RPM within acceptable range of desired
idle
²Closed throttle speed
Pending ConditionsÐThe Task Manager typi-
cally does not run the Oxygen Sensor Monitor if over-
lapping monitors are running or the MIL is
illuminated for any of the following:
²Misfire Monitor
²Front Oxygen Sensor and Heater Monitor
²MAP Sensor
25 - 2 EMISSIONS CONTROLRS
EMISSIONS CONTROL (Continued)

LEAK DETECTION PUMP MONITOR
The leak detection assembly incorporates two pri-
mary functions: it must detect a leak in the evapora-
tive system and seal the evaporative system so the
leak detection test can be run.
The primary components within the assembly are:
A three port solenoid that activates both of the func-
tions listed above; a pump which contains a switch,
two check valves and a spring/diaphragm, a canister
vent valve (CVV) seal which contains a spring loaded
vent seal valve.
Immediately after a cold start, between predeter-
mined temperature thresholds limits, the three port
solenoid is briefly energized. This initializes the
pump by drawing air into the pump cavity and also
closes the vent seal. During non test conditions the
vent seal is held open by the pump diaphragm
assembly which pushes it open at the full travel posi-
tion. The vent seal will remain closed while the
pump is cycling due to the reed switch triggering of
the three port solenoid that prevents the diaphragm
assembly from reaching full travel. After the brief
initialization period, the solenoid is de-energized
allowing atmospheric pressure to enter the pump
cavity, thus permitting the spring to drive the dia-
phragm which forces air out of the pump cavity and
into the vent system. When the solenoid is energized
and de energized, the cycle is repeated creating flow
in typical diaphragm pump fashion. The pump is con-
trolled in 2 modes:
Pump Mode:The pump is cycled at a fixed rate to
achieve a rapid pressure build in order to shorten the
overall test length.
Test Mode:The solenoid is energized with a fixed
duration pulse. Subsequent fixed pulses occur when
the diaphragm reaches the Switch closure point.
The spring in the pump is set so that the system
will achieve an equalized pressure of about 7.5º H20.
The cycle rate of pump strokes is quite rapid as the
system begins to pump up to this pressure. As the
pressure increases, the cycle rate starts to drop off. If
there is no leak in the system, the pump would even-
tually stop pumping at the equalized pressure. If
there is a leak, it will continue to pump at a rate rep-
resentative of the flow characteristic of the size of the
leak. From this information we can determine if the
leak is larger than the required detection limit (cur-
rently set at .020º orifice by CARB). If a leak is
revealed during the leak test portion of the test, the
test is terminated at the end of the test mode and no
further system checks will be performed.
After passing the leak detection phase of the test,
system pressure is maintained by turning on the
LDP's solenoid until the purge system is activated.
Purge activation in effect creates a leak. The cycle
rate is again interrogated and when it increases dueto the flow through the purge system, the leak check
portion of the diagnostic is complete.
The canister vent valve will unseal the system
after completion of the test sequence as the pump
diaphragm assembly moves to the full travel position.
Evaporative system functionality will be verified by
using the stricter evap purge flow monitor. At an
appropriate warm idle the LDP will be energized to
seal the canister vent. The purge flow will be clocked
up from some small value in an attempt to see a
shift in the 02 control system. If fuel vapor, indicated
by a shift in the 02 control, is present the test is
passed. If not, it is assumed that the purge system is
not functioning in some respect. The LDP is again
turned off and the test is ended.
DESCRIPTION - HIGH AND LOW LIMITS
The PCM compares input signal voltages from each
input device with established high and low limits for
the device. If the input voltage is not within limits
and other criteria are met, the PCM stores a diagnos-
tic trouble code in memory. Other diagnostic trouble
code criteria might include engine RPM limits or
input voltages from other sensors or switches that
must be present before verifying a diagnostic trouble
code condition.
OPERATION - SYSTEM
The Powertrain Control Module (PCM) monitors
many different circuits in the fuel injection, ignition,
emission and engine systems. If the PCM senses a
problem with a monitored circuit often enough to
indicate an actual problem, it stores a Diagnostic
Trouble Code (DTC) in the PCM's memory. If the
code applies to a non-emissions related component or
system, and the problem is repaired or ceases to
exist, the PCM cancels the code after 40 warmup
cycles. Diagnostic trouble codes that affect vehicle
emissions illuminate the Malfunction Indicator Lamp
(MIL). Refer to Malfunction Indicator Lamp in this
section.
Certain criteria must be met before the PCM
stores a DTC in memory. The criteria may be a spe-
cific range of engine RPM, engine temperature,
and/or input voltage to the PCM.
The PCM might not store a DTC for a monitored
circuit even though a malfunction has occurred. This
may happen because one of the DTC criteria for the
circuit has not been met.For example, assume the
diagnostic trouble code criteria requires the PCM to
monitor the circuit only when the engine operates
between 750 and 2000 RPM. Suppose the sensor's
output circuit shorts to ground when engine operates
above 2400 RPM (resulting in 0 volt input to the
PCM). Because the condition happens at an engine
25 - 8 EMISSIONS CONTROLRS
EMISSIONS CONTROL (Continued)

EMISSIONS CONTROL 2.5L TURBO DIESEL
TABLE OF CONTENTS
page page
EMISSIONS CONTROL 2.5L TURBO DIESEL
DESCRIPTION............................1
SPECIFICATIONS.........................2EXHAUST GAS RECIRCULATION.............3
ON-BOARD DIAGNOSTICS..................6
EMISSIONS CONTROL 2.5L
TURBO DIESEL
DESCRIPTION
The 2.5L diesel Engine Control Module (ECM) con-
trols many different circuits in the fuel injection
pump and engine systems. If the ECM senses a prob-
lem with a monitored circuit that indicates an actual
problem, a Diagnostic Trouble Code (DTC) will be
stored in the ECM's memory, and eventually may
illuminate the MIL (Malfunction Indicator Lamp)
constantly while the key is on. If the problem is
repaired, or is intermittent, the ECM will erase the
DTC after 40 warm-up cycles without the the fault
detected. A warm-up cycle consists of starting the
vehicle when the engine is cold, then the engine is
warmed up to a certain temperature, and finally, the
engine temperature falls to a normal operating tem-
perature, then the key is turned off.
Certain criteria must be met for a DTC to be
entered into ECM memory. The criteria may be a
specific range of engine rpm, engine or fuel tempera-
ture and/or input voltage to the ECM. A DTC indi-
cates that the ECM has identified an abnormal
signal in a circuit or the system.
There are several operating conditions that the
ECM does not monitor and set a DTC for. Refer to
the following Monitored Circuits and Non±Monitored
Circuits in this section.
ECM MONITORED SYSTEMS
The ECM can detect certain problems in the elec-
trical system.
Open or Shorted Circuit± The ECM will not
distinguish between an open or a short to ground,
however the ECM can determine if there is excessive
current on a circuit, such as a short to voltage or a
decrease in component resistance.
Output Device Current Flow± The ECM senses
whether the output devices are electrically connected.
If there is a problem with the circuit, the ECM
senses whether the circuit is open, shorted to ground
(±), or shorted to (+) voltage.Fuel Pressure:Fuel pressure is controlled by the
fuel injection pump and fuel pressure solenoid. The
ECM uses a fuel pressure sensor to determine if a
fuel pressure problem exists.
Fuel Injector Malfunctions:The ECM can deter-
mine if a fuel injector has an electrical problem. The
fuel injectors on the diesel engine arecontrolledby
the ECM.
ECM NON±MONITORED SYSTEMS
The ECM does not monitor the following circuits,
systems or conditions that could have malfunctions
that result in driveability problems. A DTC will not
be displayed for these conditions.
Cylinder Compression:The ECM cannot detect
uneven, low, or high engine cylinder compression.
Exhaust System:The ECM cannot detect a
plugged, restricted or leaking exhaust system.
Vacuum Assist:Leaks or restrictions in the vac-
uum circuits of the Exhaust Gas Recirculation Sys-
tem (EGR) are not monitored by the ECM.
ECM System Ground:The ECM cannot deter-
mine a poor system ground. However, a DTC may be
generated as a result of this condition.
ECM/PCM Connector Engagement:The ECM
cannot determine spread or damaged connector pins.
However, a DTC may be generated as a result of this
condition.
HIGH AND LOW LIMITS
The ECM compares input signals from each input
device. It has high and low limits that are pro-
grammed into it for that device. If the inputs are not
within specifications and other DTC criteria are met,
a DTC will be stored in memory. Other DTC criteria
might include engine rpm limits or input voltages
from other sensors or switches. The other inputs
might have to be sensed by the ECM when it senses
a high or low input voltage from the control system
device in question.
RGEMISSIONS CONTROL 2.5L TURBO DIESEL25a-1