reset CHRYSLER VOYAGER 2001 Service Manual

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)

GEARSHIFT CABLE ADJUSTMENT
Lift and rotate the gearshift hand lever into the
park (P) gate position and remove the ignition key.
This confirms the shift lever is in the gated park (P)
position.
After confirming the park gate position, turn the
ignition switch . If the starter will operate, the park
gate position is correct. Move the shift lever into the
neutral (N) position. If the starter will operate in this
position, the linkage is properly adjusted. If the
starter fails to operate in either position, linkage
adjustment is required.
(1) Park the vehicle on level ground and set the
parking brake.
(2) Place the gearshift lever in park (P) gate posi-
tion and remove key.
(3) Loosen the cable adjustment screw at the
transaxle operating lever (Fig. 181).
(4) Pull the transaxle operating lever fully forward
to the park detent position.
(5) Release the park brake, then rock the vehicle
to assure it is in park lock. Reset the park brake.
(6) Tighten the cable adjustment screw to 8 N´m
(70 in. lbs.). Gearshift cable should now be properly
adjusted.
(7) Verify PRNDL indicator still displays the corre-
sponding gear completely. If not, readjustment of
PRNDL may be required.(8) Check adjustment by using the preceding pro-
cedure.
GOVERNOR
DESCRIPTION
The governor assembly is fastened to the transaxle
transfer shaft. It consists of a governor body, weight,
valve, and shaft.
OPERATION
The governor meters hydraulic pressure, and this
metered pressure is used to signal the transmission
when it is time for a shift to occur. It does this by
balancing governor pressure on one side of a shift
valve, and throttle pressure on the other. When gov-
ernor pressure increases far enough to overcome the
throttle pressure on the valve, a shift occurs.
With the gearshift selector in a forward driving
range, line pressure flows from the manual valve and
down to the governor valve. When the output shaft
starts to rotate with vehicle motion, the governor
weight assembly will start to move outward due to
centrifugal force. As the weight is moved outward, it
will pull the valve with it until the land of the valve
uncovers the line pressure port. As the port begins to
become uncovered, governor pressure is metered. As
the vehicle's speed continues to increase, the weight
assembly will be at a point at which governor pres-
sure is acting on the left side of the reaction area of
the valve. This produces sufficient force to compress
the spring and allow the outer weight to move out
against the outer governor body retaining ring. At a
very high speed, the governor valve will be opened as
far as possible. In this condition, it is possible for
governor pressure to meet, but not to exceed, line
Fig. 180 Gearshift Cable at Transaxle
1 - MANUAL VALVE LEVER
2 - GEAR SHIFT CABLE
3 - UPPER MOUNT BRACKET
Fig. 181 Gearshift Cable Adjustment
1 - SHIFT CABLE ADJUSTMENT
2 - SHIFT CABLE
RSAUTOMATIC - 31TH21 - 103
GEAR SHIFT CABLE (Continued)

Converter housing leaks have several potential
sources. Through careful observation, a leak source
can be identified before removing the transmission
for repair.
Pump seal leaks tend to move along the drive hub
and onto the rear of the converter (Fig. 6). Pump
o-ring or pump body leaks follow the same path as a
seal leak. Pump attaching bolt leaks are generally
deposited on the inside of the converter housing and
not on the converter itself. Pump seal or gasket leaks
usually travel down the inside of the converter hous-
ing (Fig. 6).
TORQUE CONVERTER LEAKAGE
Possible sources of torque converter leakage are:
²Torque converter weld leaks at the outside diam-
eter weld (Fig. 7).
²Torque converter hub weld (Fig. 7).
REMOVAL
NOTE: If transaxle assembly is being replaced or
overhauled (clutch and/or seal replacement), it is
necessary to perform the TCM Quick Learn Proce-
dure. (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/TRANSMISSION CONTROL
MODULE - STANDARD PROCEDURE)NOTE: If the torque converter assembly is being
replaced, it is necessary to reset the TCC Break-In
Strategy. (Refer to 8 - ELECTRICAL/ELECTRONIC
CONTROL MODULES/TRANSMISSION CONTROL
MODULE - STANDARD PROCEDURE)
(1) Disconnect battery cables.
(2) Remove battery shield (Fig. 8).
(3) Remove coolant recovery bottle (Fig. 9).
Fig. 6 Converter Housing Leak Paths
1 - PUMP SEAL
2 - PUMP VENT
3 - PUMP BOLT
4 - PUMP GASKET
5 - CONVERTER HOUSING
6 - CONVERTER
7 - REAR MAIN SEAL LEAK
Fig. 7 Converter Leak Points - Typical
1 - OUTSIDE DIAMETER WELD
2 - TORQUE CONVERTER HUB WELD
3 - STARTER RING GEAR
4 - LUG
Fig. 8 Battery Thermal Guard
1 - BATTERY THERMAL GUARD
2 - INTELLIGENT POWER MODULE
3 - FRONT CONTROL MODULE
RSAUTOMATIC - 41TE21 - 165
AUTOMATIC - 41TE (Continued)

INSTALLATION
NOTE: If transaxle assembly has been replaced or
overhauled (clutch and/or seal replacement), it is
necessary to perfrom the TCM Quick Learn proce-
dure. (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/TRANSMISSION CONTROL
MODULE - STANDARD PROCEDURE)
NOTE: If torque converter assembly has been
replaced, it is necessary to reset the TCC Break-In
Strategy. (Refer to 8 - ELECTRICAL/ELECTRONIC
CONTROL MODULES/TRANSMISSION CONTROL
MODULE - STANDARD PROCEDURE)
(1) Using a transmission jack and a helper, posi-
tion transaxle assembly to engine. Install and torque
bolts to 95 N´m (70 ft. lbs.).
(2) Install upper mount assembly to transaxle and
torque bolts to 54 N´m (40 ft. lbs.) (Fig. 164).
(3) Raise engine/transaxle assembly into position.
Install and torque upper mount-to-bracket thru-bolt
to 75 N´m (55 ft. lbs.) (Fig. 164).
(4) Remove transmission jack and screw jack.
(5) Secure left wheelhouse splash shield.
(6) Install torque converter-to-drive plate bolts and
torque to 88 N´m (65 ft. lbs.)
(7) Install inspection cover.(8) Install lateral bending brace.
(9) Install starter motor.
(10) Install front mount/bracket assembly.
(11) Install rear mount and bracket assembly into
position (Fig. 165).
(12) Install and torque rear mount bolts to 54 N´m
(40 ft. lbs.) (Fig. 166).
(13) Lower vehicle.
(14) Install and torque rear mount bracket-to-tran-
saxle vertical bolts (Fig. 165) to 102 N´m (75 ft. lbs.).
(15) Raise vehicle.
(16) Install rear mount bracket-to-transaxle hori-
zontal bolt (Fig. 165) and torque to 102 N´m (75 ft.
lbs.).
(17) Install rear mount thru-bolt and torque to 54
N´m (40 ft. lbs.) (Fig. 166).
(18) Install rear mount heat shield (Fig. 167).
(19) AWD models: Install power transfer unit.
(Refer to 21 - TRANSMISSION/TRANSAXLE/
POWER TRANSFER UNIT - INSTALLATION)
(20) Install cradle plate.
(21) Install exhaust pipe to manifold (Fig. 168).
(22) Install left and right halfshaft assemblies.
(Refer to 3 - DIFFERENTIAL & DRIVELINE/HALF
SHAFT - INSTALLATION)
(23) Install front wheel/tire assemblies.
(24) Lower vehicle.
(25) Install transaxle upper bellhousing-to-block
bolts and torque to 95 N´m (70 ft. lbs.).
(26) Install wiper module assembly. (Refer to 8 -
ELECTRICAL/WIPERS/WASHERS/WIPER MOD-
ULE - INSTALLATION)
(27) Connect crank position sensor (if equipped).
(28) Connect gearshift cable to upper mount
bracket and transaxle manual valve lever (Fig. 169).
(29) Connect solenoid/pressure switch assembly
(Fig. 170).
(30) Connect transmission range sensor connector
(Fig. 170).
(31) Connect input and output speed sensor con-
nectors (Fig. 170).
(32) Remove plugs and install transaxle oil cooler
line service splice kit. Refer to instructions included
with kit.
(33) Remove plug and Install fluid level indicator/
tube assembly.
(34) Install coolant recovery bottle (Fig. 171).
(35) Install battery shield.
(36) Connect battery cables.
(37) Fill transaxle with suitable amount of ATF+4
(Automatic Transmission FluidÐType 9602). (Refer
to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC
- 41TE/FLUID - STANDARD PROCEDURE)
Fig. 164 Left Mount to Bracket and Transaxle
1 - BOLT - BRACKET TO FRAME RAIL 68 N´m (50 ft. lbs.)
2 - BOLT - MOUNT TO RAIL THRU 75 N´m (55 ft. lbs.)
3 - BOLT - LEFT MOUNT TO TRANSAXLE 54 N´m (40 ft. lbs.)
4 - TRANSAXLE
5 - MOUNT - LEFT
6 - BRACKET - LEFT MOUNT
RSAUTOMATIC - 41TE21 - 209
AUTOMATIC - 41TE (Continued)

GEARSHIFT CABLE ADJUSTMENT
VERIFICATION
(1) Place gearshift lever in gated park (P).
(2) Attempt to move vehicle by rocking back and
forth on level ground. If vehicle does not move,
attempt to start engine. If engine starts, the park
position is correct.
(3) Set parking brake.
(4) Turn key to on/run and depress brake pedal.
Place gearshift lever in neutral (N).
(5) Attempt to start engine. If engine starts in
both neutral (N) or park (P), gearshift cable is
adjusted properly. No adjustment is required.
(6) If engine does not start in either park (P) or
neutral (N), perform adjustment procedure.
ADJUSTMENT
(1) Park the vehicle on level ground and set the
parking brake.
(2) Place the gearshift lever in gated park (P) and
remove ignition key.
(3) Loosen the cable adjustment screw at the
transaxle manual valve lever (Fig. 228).(4) Pull the gearshift lever fully forward to the
park detent position.
(5) Release the park brake, then rock the vehicle
to assure it is in park. Reset the park brake.
(6) Tighten the cable adjustment screw to 8 N´m
(70 in. lbs.). Gearshift cable should now be properly
adjusted.
(7) Verify adjustment by using the verification pro-
cedure.
HOLDING CLUTCHES
DESCRIPTION
Two hydraulically applied multi-disc clutches are
used to hold planetary geartrain components station-
ary while the input clutches drive others. The 2/4
and Low/Reverse clutches are considered holding
clutches and are contained at the rear of the trans-
axle case. (Fig. 229) .
OPERATION
NOTE: Refer to the ªElements In Useº chart in Diag-
nosis and Testing for a collective view of which
clutch elements are applied at each position of the
selector lever.
2/4 CLUTCH
The 2/4 clutch is hydraulically applied in second
and fourth gears by pressurized fluid against the 2/4
clutch piston. When the 2/4 clutch is applied, the
front sun gear assembly is held or grounded to the
transaxle case.
Fig. 227 Gearshift Cable at Transaxle
1 - MANUAL VALVE LEVER
2 - GEAR SHIFT CABLE
3 - UPPER MOUNT BRACKET
Fig. 228 Gearshift Cable Adjustment
1 - GEARSHIFT CABLE ADJUSTMENT SCREW
2 - GEARSHIFT CABLE
RSAUTOMATIC - 41TE21 - 251
GEAR SHIFT CABLE (Continued)

The engagement and disengagement of the TCC
are automatic and controlled by the Powertrain Con-
trol Module (PCM). The engagement cannot be acti-
vated in the lower gears because it eliminates the
torque multiplication effect of the torque converter
necessary for acceleration. Inputs that determine
clutch engagement are: coolant temperature, vehicle
speed and throttle position. The torque converter
clutch is engaged by the clutch solenoid on the valve
body. The clutch will engage at approximately 56
km/h (35 mph) with light throttle, after the shift to
third gear.
REMOVAL
NOTE: If torque conveter assembly is being
replaced, it is necessary to restart the TCC Break-In
Strategy. (Refer to 8 - ELECTRICAL/ELECTRONIC
CONTROL MODULES/TRANSMISSION CONTROL
MODULE - STANDARD PROCEDURE)
(1) Remove transmission and torque converter
from vehicle. (Refer to 21 - TRANSMISSION/TRANS-
AXLE/AUTOMATIC - 41TE - REMOVAL)
(2) Place a suitable drain pan under the converter
housing end of the transmission.
CAUTION: Verify that transmission is secure on the
lifting device or work surface, the center of gravity
of the transmission will shift when the torque con-
verter is removed creating an unstable condition.
The torque converter is a heavy unit. Use caution
when separating the torque converter from the
transmission.
(3) Pull the torque converter forward until the cen-
ter hub clears the oil pump seal.
(4) Separate the torque converter from the trans-
mission.
INSTALLATION
NOTE: If torque conveter is being replaced, it is
necessary to restart the TCC Break-In Strategy.
(Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL
MODULES/TRANSMISSION CONTROL MODULE -
STANDARD PROCEDURE)
Check converter hub and drive notches for sharp
edges, burrs, scratches, or nicks. Polish the hub and
notches with 320/400 grit paper or crocus cloth if nec-
essary. The hub must be smooth to avoid damaging
the pump seal at installation.
(1) Lubricate converter hub and oil pump seal lip
with transmission fluid.
(2) Place torque converter in position on transmis-
sion.CAUTION: Do not damage oil pump seal or bushing
while inserting torque converter into the front of the
transmission.
(3) Align torque converter to oil pump seal open-
ing.
(4) Insert torque converter hub into oil pump.
(5) While pushing torque converter inward, rotate
converter until converter is fully seated in the oil
pump gears.
(6) Check converter seating with a scale and
straightedge (Fig. 339). Surface of converter lugs
should be 1/2 in. to rear of straightedge when con-
verter is fully seated.
(7) If necessary, temporarily secure converter with
C-clamp attached to the converter housing.
(8) Install the transmission in the vehicle. (Refer
to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC
- 41TE - INSTALLATION)
(9) Fill the transmission with the recommended
fluid. (Refer to 21 - TRANSMISSION/TRANSAXLE/
AUTOMATIC - 41TE/FLUID - STANDARD PROCE-
DURE)
(10) If torque conveter was replaced, it is neces-
sary to reset the TCC Break-In Strategy. (Refer to 8 -
ELECTRICAL/ELECTRONIC CONTROL MOD-
ULES/TRANSMISSION CONTROL MODULE -
STANDARD PROCEDURE)
Fig. 339 Checking Torque Converter Seating
1 - SCALE
2 - STRAIGHTEDGE
21 - 286 AUTOMATIC - 41TERS
TORQUE CONVERTER (Continued)

TRANSMISSION CONTROL
RELAY
DESCRIPTION
The transmission control relay (Fig. 340) is located
in the Intelligent Power Module (IPM), which is
located on the left side of the engine compartment
between the battery and left fender.
OPERATION
The relay is supplied fused B+ voltage, energized
by the TCM, and is used to supply power to the sole-
noid pack when the transmission is in normal oper-
ating mode. When the relay is ªoffº, no power is
supplied to the solenoid pack and the transmission is
in ªlimp-inº mode. After a controller reset (ignition
key turned to the ªrunº position or after cranking
engine), the TCM energizes the relay. Prior to this,
the TCM verifies that the contacts are open by check-
ing for no voltage at the switched battery terminals.
After this is verified, the voltage at the solenoid pack
pressure switches is checked. After the relay is ener-
gized, the TCM monitors the terminals to verify that
the voltage is greater than 3 volts.
TRANSMISSION RANGE
SENSOR
DESCRIPTION
The Transmission Range Sensor (TRS) is mounted
to the top of the valve body inside the transaxle and
can only be serviced by removing the valve body. The
electrical connector extends through the transaxle
case (Fig. 341) .
The Transmission Range Sensor (TRS) has four
switch contacts that monitor shift lever position and
send the information to the TCM.
The TRS also has an integrated temperature sen-
sor (thermistor) that communicates transaxle tem-
perature to the TCM and PCM (Fig. 342) .
OPERATION
The Transmission Range Sensor (TRS) (Fig. 341)
communicates shift lever position (SLP) to the TCM
as a combination of open and closed switches. Each
shift lever position has an assigned combination of
switch states (open/closed) that the TCM receives
from four sense circuits. The TCM interprets this
information and determines the appropriate trans-
axle gear position and shift schedule.
Fig. 340 Transmission Control Relay Location
1 - TRANSMISSION CONTROL RELAY
2 - LEFT FENDER
3 - INTELLIGENT POWER MODULE (IPM)
4 - BATTERYFig. 341 Transmission Range Sensor (TRS)
Location
1 - TRANSMISSION RANGE SENSOR
RSAUTOMATIC - 41TE21 - 287

3.2.3 OTHER CONTROLS
CHARGING SYSTEM
The charging system is turned on when the
engine is started and ASD relay energized. When
the ASD relay is on, ASD output voltage is supplied
to the ASD sense circuit at the PCM. This voltage is
connected in some cases, through the PCM and
supplied to one of the generator field terminals
(Gen Source +). All others, the Gen field is con-
nected directly to the ASD output voltage. The
amount of current produced by the generator is
controlled by the Electronic Voltage Regulator
(EVR) circuitry, in the PCM. Battery temperature is
determined from IAT. This temperature along with
sensed line voltage, is used by the PCM to vary the
battery charging rate. This is done by cycling the
ground path to the other generator field terminal
(Gen field driver).
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 dump
solenoid allows immediate release of throttle posi-
tion caused by braking, cruise control switch turned
off, shifting into neutral, excessive RPM (tires spin-
ning) or ignition off.
LEAK DETECTION PUMP SYSTEM (IF EQUIPPED)
The leak detection pump is a device that pressur-
izes the evaporative system to determine if there
are any leaks. When certain conditions are met, the
PCM will activate the pump and start counting
pump strokes. If the pump stops within a calibrated
number of strokes, the system is determined to be
normal. If the pump does not stop or stops too soon,
a DTC will be set.
3.2.4 PCM OPERATING MODES
As input signals to the PCM change, the PCM
adjusts its response to output devices. For example,
the PCM must calculate a different injector pulse
width and ignition timing for idle than it does for
wide open throttle. There are several different
modes of operation that determine how the PCM
responds to the various input signals.
There are two types of engine control operation:
open loopandclosed loop.
Inopen loopoperation, the PCM receives input
signals and responds according to preset program-
ming. Inputs from the heated oxygen sensors are
not monitored.Inclosed loopoperation, the PCM monitors the
inputs from the heated oxygen sensors. This input
indicates to the PCM whether or not the calculated
injector pulse width results in the ideal air-fuel
ratio of 14.7 parts air to 1 part fuel. By monitoring
the exhaust oxygen content through the oxygen
sensor, the PCM can fine tune injector pulse width.
Fine tuning injector pulse width allows the PCM to
achieve the lowest emission levels while maintain-
ing optimum fuel economy.
The engine start-up (crank), engine warm-up,
and wide open throttle modes are open loop modes.
Under most operating conditions, closed loop modes
occur with the engine at operating temperature.
IGNITION SWITCH ON (ENGINE OFF) MODE
When the ignition switch activates the fuel injec-
tion system, the following actions occur:
1. The PCM determines atmospheric air pressure
from the MAP sensor input to determine basic
fuel strategy.
2. The PCM monitors the engine coolant tempera-
ture sensor and throttle position sensor input.
The PCM modifies fuel strategy based on this
input.
When the key is in the on position and the engine
is not running (zero rpm), the auto shutdown relay
and fuel pump relay are not energized. Therefore,
voltage is not supplied to the fuel pump, ignition
coil, and fuel injectors.
Engine Start-up ModeÐ This is an open loop
mode. The following actions occur when the starter
motor is engaged:
1. The auto shutdown and fuel pump relays are
energized. If the PCM does not receive the cam-
shaft and crankshaft signal within approxi-
mately one second, these relays are de-
energized.
2. The PCM energizes all fuel injectors until it
determines crankshaft position from the cam-
shaft and crankshaft signals. The PCM deter-
mines crankshaft position within one engine
revolution. After the camshaft position has been
determined, the PCM energizes the fuel injectors
in sequence. The PCM adjusts the injector pulse
width and synchronizes the fuel injectors by
controlling the fuel injectors' ground paths.
3. Once the engine idles within 64 rpm of its target
engine speed, the PCM compares the current
MAP sensor value with the value received dur-
ing the ignition switch on (zero rpm) mode. A
diagnostic trouble code is written to PCM mem-
ory if a minimum difference between the two
values is not found.
4
GENERAL INFORMATION

powertrain control module checks that circuit or
function. Procedures in this manual verify if the
DTC is a hard code at the beginning of each test.
When it is not a hard code, an intermittent test
must be performed.
DTC's that are for Euro Stage III OBD monitors
will not set with just the ignition key on. Comparing
these to non-emission DTC's, they will seem like an
intermittent. These DTC's require a set of parame-
ters to be performed (The DRBIIItpre-test screens
will help with this for MONITOR DTC's), this is
called a TRIP. All Euro Stage III OBD DTCs will be
set after one or in some cases two trip failures, and
the MIL will be turned on. These DTC's require
three successful, no failures, TRIPS to extinguish
the MIL, followed by 40 warm-up cycles to erase the
DTC.
3.3.2 INTERMITTENT CODE
A diagnostic trouble code that is not there every
time the PCM checks the circuit is an intermittent
DTC. Most intermittent DTC's are caused by wiring
or connector problems. Defects that come and go
like this are the most difficult to diagnose; they
must be looked for under specific conditions that
cause them. The following checks may assist you in
identifying a possible intermittent problem:
²Visually inspect related wire harness connectors.
Look for broken, bent, pushed out, or corroded
terminals.
²Visually inspect the related harnesses. Look for
chafed, pierced, or partially broken wire.
²Refer to any technical service bulletins that may
apply.
²Use the DRBIIItdata recorder or co-pilot.
3.3.3 DISTANCE SINCE MI SET
The Euro Stage III OBD directive requires that
the distance traveled by the vehicle while theMIis
activated must be available at any instant through
the serial port on the standard data link connector.
This feature works as follows:1. If the MI is illuminated due to a fault, the
distance count is updated (i.e. it is counting).
2. If there is a9stale9MI fault (i.e. the fault is still
frozen in memory but the MI has heen extin-
guished due to 3 good trips), the distance count is
held (i.e. frozen).
3. If the distance count is being held due to (Item
2.) and the fault is cleared, the distance is
cleared (set to zero).
4. If the distance count is being held due to (Item
2.) and another MI occurs, the distance count is
reset (to 0) and begins updating anew.
5. If a fault occurs while the MI is already illumi-
nated due to a previous fault (the distance count
is updating), then the distance count continues
to update w/out interruption.
6. If the MI is flashing due to activate misfire and
there is and9active9fault (i.e. matured fault for
which 3 good trips have not occurred), the dis-
tance count behaves as the MI in ON.
7. If the MI is flashing due to active misfire and
there is no9active9fault (i.e. the MI is flashing
for a 1 malf.), the distance count behaves as if
the MI is off (because it is not yet a matured
fault).
8. The distance count is cleared whenever the fault
is cleared. (Via 40 warm up cycles, or via scan
tool).
3.3.4 HANDLING NO DTC PROBLEMS
Symptom checks cannot be used properly unless
the driveability problem characteristic actually
happens while the vehicle is being tested.
Select the symptom that most accurately de-
scribes the vehicle's driveability problem and then
perform the test routine that pertains to this symp-
tom. Perform each routine test in sequence until the
problem is found. For definitions, see Section 6.0
Glossary Of Terms.
SYMPTOM DIAGNOSTIC TEST
HARD START CHECKING THE FUEL PRESSURE
CHECKING THE ECT SENSOR
CHECKING THROTTLE POSITION SENSOR
CHECKING MAP SENSOR
CHECKING IDLE AIR CONTROL MOTOR OPERATION
CHECKING EGR SYSTEM
CHECKING IAT SENSOR
8
GENERAL INFORMATION

Symptom:
P0622-GENERATOR FIELD NOT SWITCHING PROPERLY
When Monitored and Set Condition:
P0622-GENERATOR FIELD NOT SWITCHING PROPERLY
When Monitored: With the ignition on. Engine running.
Set Condition: When the PCM tries to regulate the generator field with no result during
monitoring.
POSSIBLE CAUSES
WIRING HARNESS INTERMITTENT
INSPECT WIRING HARNESS
ASD RELAY OUTPUT CIRCUIT OPEN
GENERATOR FIELD DRIVER CIRCUIT SHORTED TO GROUND
GENERATOR FIELD DRIVER CIRCUIT OPEN
GENERATOR
POWERTRAIN CONTROL MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRBIIIt, actuate the Generator Field Driver circuit.
Using a 12-volt test light connected to ground, backprobe the Generator Field Driver
circuit in the back of the Generator.
Does the test light illuminate brightly and flash?All
Ye s®Go To 2
No®Go To 4
2 Turn the ignition on.
With the DRBIIItactuate the Generator Field Driver circuit.
Wiggle the wiring harness from the Generator to PCM.
With the DRBIIIt, read DTC's.
Did the DTC reset?All
Ye s®Repair as necessary .
Perform POWERTRAIN VERIFICATION TEST VER - 3.
No®Go To 3
3 Turn the ignition off.
Using the schematic as a guide, inspect the Wiring and Connectors.
Were any problems found?All
Ye s®Repair as necessary.
Perform POWERTRAIN VERIFICATION TEST VER - 3.
No®Test Complete.
16
CHARGING