2001 CHRYSLER VOYAGER air condition

POWERTRAIN VERIFICATION TEST VER-1 APPLICABILITY
1. NOTE: If the PCM has been replaced and the correct VIN and mileage have not
been programmed, a DTC will be set in the ABS Module, Airbag Module and the
SKIM.
2. NOTE: If the vehicle is equipped with a Sentry Key Immobilizer System, Secret
Key data must be updated. Refer to the Service Information for the PCM, SKIM and
the Transponder (ignition key) for programming information.
3. Inspect the vehicle to ensure that all components related to the repair are connected
properly.
4. Inspect the engine oil for fuel contamination. Replace the oil and filter as necessary.
5. Attempt to start the engine.
6. If the No Start condition is still present, refer to the symptom list and perform the diagnostic
testing as necessary. refer to and Technical Service Bulletins that may apply.
7. Run the engine for one warm-up cycle to verify operation.
8. With the DRBIIIt, confirm that no DTCs or Secondary Indicators are present and that all
components are functioning properly.
9. If a DTC is present, refer to the appropriate category and select the corresponding symptom.
Are any DTCs present?All
Ye s®Repair is not complete, refer to appropriate symptom.
No®Repair is complete.
SKIS VERIFICATION APPLICABILITY
1. Reconnect all previously disconnected components and connectors.
2. Obtain the vehicle's unique Personal Identification Number (PIN) assigned to it's original
SKIM. This number can be obtained from the vehicle's invoice or Chrysler's Customer Center
(1-800-992-1997).
3. NOTE: When entering the PIN, care should be taken because the SKIM will only
allow 3 consecutive attempts to enter the correct PIN. If 3 consecutive incorrect
PIN's are entered the SKIM will Lock Out the DRB III for 1 hour.
4. To exit Lock Out mode, the ignition key must remain in the Run position continually for 1
hour. Turn off all accessories and connect a battery charger if necessary.
5. With the DRB III, select Theft Alarm, SKIM and Miscellaneous. Then select desired
procedure and follow the steps that will be displayed.
6. If the SKIM has been replaced, ensure all of the vehicle ignition keys are programmed to the
new SKIM.
7. NOTE: Prior to returning vehicle to the costumer, perform a module scan to be
sure that all DTC's are erased. Erase any DTC's that are found.
8. With the DRB III erase all DTC's. Perform 5 ignition key cycles leaving the key on for at least
90 seconds per cycle.
9. With the DRB III, read the SKIM DTC's.
Are there any SKIM DTC's?All
Ye s®Repair is not complete, refer to appropriate symptom.
No®Repair is complete.
281
VERIFICATION TESTS
VERIFICATION TESTS ÐContinued

1.0 INTRODUCTION
The procedures contained in this manual include
all of the specifications, instructions, and graphics
needed to diagnose 41TE/AE Electronic Automatic
Transaxle (EATX) problems. The diagnostics in this
manual are based on the failure condition or symp-
tom being present at the time of diagnosis.
When repairs are required, refer to the appropri-
ate volume of the service manual for the proper
removal and repair procedure.
Diagnostic procedures change every year. New
diagnostic systems may be added and/or carryover
systems may be enhanced. READ THIS MANUAL
BEFORE TRYING TO DIAGNOSE A VEHICLE
TROUBLE CODE. It is recommended that you
review the entire manual to become familiar with
all new and changed diagnostic procedures.
This book reflects many suggested changes from
readers of past issues. After using this book, if you
have any comments or recommendations, please fill
out the form at the back of the book and mail it back
to us.
1.1 SYSTEM COVERAGE
This diagnostic procedures manual covers all
2001 RG equipped with a 41TE/AE transaxle.
1.2 SIX -STEP TROUBLESHOOTING
PROCEDURE
Diagnosis of the 41TE/AE electronic transaxle is
done in six basic steps:
verification of complaint
verification of any related symptoms
symptom analysis
problem isolation
repair of isolated problem
verification of proper operation
2.0 IDENTIFICATION OF
SYSTEM
RG series vehicles equipped with a 4 speed trans-
mission.
3.0 SYSTEM DESCRIPTION AND
FUNCTIONAL OPERATION
3.1 GENERAL DESCRIPTION
The 41TE/AE electronic transaxle is a conven-
tional transaxle in that it uses hydraulically ap-
plied clutches to shift a planetary gear train. How-
ever, the electronic control system replaces many of
the mechanical and hydraulic components used in
conventional transmission valve bodies.
3.2 FUNCTIONAL OPERATION
The 41TE/AE electronic transaxle has a fully
adaptive control system. The system performs it's
functions based on continuous real-time sensor
feedback information. The control system automat-
ically adapts to changes in engine performance and
friction element variations to provide consistent
shift quality. The control system ensures that clutch
operation during upshifting and downshifting is
more responsive without increased harshness.
The Transmission Control Module (TCM) contin-
uously checks for electrical problems, mechanical
problems, and some hydraulic problems. When a
problem is sensed, the TCM stores a diagnostic
trouble code. Some of these codes cause the tran-
saxle to go into limp-in or default mode.
While in this mode, electrical power is taken
away from the transaxle via the TCM, de-
energizing the transmission control relay, and tak-
ing power from the solenoid pack. When this hap-
pens, the only transaxle mechanical functions are:
Park and Neutral
Reverse
Second Gear
No upshifts or downshifts are possible. The posi-
tion of the manual valve alone allows the three
ranges that are available. Although vehicle perfor-
mance is seriously degraded while in this mode, it
allows the owner to drive the vehicle in for service.
Once the DRBIIItis in the EATX portion of the
diagnostic program, it constantly monitors the
TCM to see if the system is in limp-in mode. If the
transaxle is in limp-in mode, the DRBIIIž will flash
the red LED.
3.2.1 AUTOSTICK FEATURE
This feature allows the driver to manually shift
the transaxle when the shift lever is pulled back
into the AutoStick position. When in AutoStick
mode, the instrument cluster displays the current
gear.
1
GENERAL INFORMATION

> Trailer towing in OD gear position (use 3 position
(or A/S 3rd) if frequent shifting occurs)
> Cooling system failure causing engine to operate
over 110C (230ÉF)
> Engine coolant temperature stays low too long -
If engine coolant temperature drops below 65C
(150ÉF), the transmission will disengage EMCC.
Extended operation with the EMCC disengaged
will cause the transmission to overheat.
> A brake switch issue will cause the EMCC to
disengage. Extended operation with the EMCC
disengaged will cause the transmission to over-
heat.
> Transmission fluid overfilled
> Transmission cooler or cooler lines restricted
> Transmission Temperature Sensor circuit
3.3 DIAGNOSTIC TROUBLE CODES
Diagnostic trouble codes (DTC's) are codes stored
by the Transmission Control Module (TCM) that
help us diagnose Transmission problems. They are
viewed using the DRBIIItscan tool.
Always begin by performing a visual inspection of
the wiring, connectors, cooler lines and the trans-
mission. Any obvious wiring problems or leaks
should be repaired prior to performing any diagnos-
tic test procedures. Some engine driveability prob-
lems can be misinterpreted as a transmission prob-
lem. Ensure that the engine is running properly
and that no PCM DTC's are present that could
cause a transmission complaint.
If there is a communication bus problem, trouble
codes will not be accessible until the problem is
fixed. The DRBIIItwill display an appropriate
message. The following is a possible list of causes
for a bus problem:
± open or short to ground/battery in PCI bus
circuit (pin 43).
± internal failure of any module or component on
the bus
Each diagnostic trouble code is diagnosed by
following a specific testing sequence. The diagnostic
test procedures contain step-by-step instructions
for determining the cause of a transmission diag-
nostic trouble code. Possible sources of the code are
checked and eliminated one by one. It is not neces-
sary to perform all of the tests in this book to
diagnose an individual code. These tests are based
on the problem being present at the time that the
test is run.All testing should be done with a
fully charged battery.
If the TCM records a DTC that will adversely
affect vehicle emissions, it will request (via the
communication bus) that the PCM illuminate the
Malfunction Indicator Lamp (MIL). Although theseDTC's will be stored in the TCM immediately as a 1
trip failure, it may take up to five minutes of
accumulated trouble confirmation set the DTC and
illuminate the MIL. Three consecutive successful
OBDII (EURO STAGE III OBD) trips or clearing
the DTC's with a diagnostic tool (DRBIIItor equiv-
alent) is required to extinguish the MIL. When the
TCM requests that the PCM illuminate the MIL,
the PCM sets a DTC P0700(89) to alert the techni-
cian that there are DTC's in the TCM. This must
also be erased in the PCM in order to extinguish the
MIL.
3.3.1 HARD CODE
Any Diagnostic Trouble Code (DTC) that is set
whenever the system or component is monitored is
a HARD code. This means that the problem is there
every time the TCM checks that system or compo-
nent. Some codes will set immediately at start up
and others will require a road test under specific
conditions. It must be determined if a code is
repeatable (Hard) or intermittent before attempt-
ing diagnosis.
3.3.2 ONE TRIP FAILURES
A One Trip Failure, when read from the TCM, is
a hard OBDII (EURO STAGE III OBD) code that
has not matured for the full 5 minutes. This applies
to codes that will only set after 5 minutes of
substituted gear operation.
3.3.3 INTERMITTENT CODE
A diagnostic trouble code that is not there every
time the TCM checks the circuit or function is an a
intermittent code. Some intermittent codes, such as
codes P1792(12), P1767(14), P1768(15), P0725(18),
P1716(19), P1781(21), P1782(22), P1724(24),
P0705(28), P0120(29), P0750(41), P0755(42),
P0760(43), P0765(44), P1793(48), P0715(56),
P0720(57), P1794(58), P1796(70), P1799(74),
P1739(76), P1717(77), and P0600(78) are caused by
wiring or connector problems. However intermit-
tent codes 50 - 54 are usually caused by intermit-
tent hydraulic seal leakage in the clutch and/or
accumulator circuits. Problems that come and go
like this are the most difficult to diagnose, they
must be looked for under the specific conditions
that cause them.
3.3.4 STARTS SINCE SET COUNTER
For the most recent code (Code 1), the Starts
Since Set counter counts the number of times the
vehicle has started since it was last set. The counter
will count up to 255 starts. Note that this code only
applies to the last code set.
When there are no diagnostic trouble codes stored
in memory, the DRBIIItwill display ``NO DTC'S
3
GENERAL INFORMATION

responding element is applied. If a switch fails to
close, it is retested, If it fails the second test, the
code is set.
Transmission Effects:The MIL illuminates and
the transmission system defaults to Relay Open
limp-in mode.
Possible causes:
> Pressure switch sense circuit shorted to battery
between TCM and solenoid pack.
> Low line pressure
> Solenoid Pack
Name of code:P1791(35) - Loss Of Prime
When monitored:If the transmission is slipping
in any forward gear and the pressure switches are
not indicating pressure, a loss of prime test is run.
Set condition:If the transmission begins to slip in
any forward gear, and the pressure switch or
switches that should be closed for a given gear are
open, a loss of prime test begins. All available
elements (in 1st gear L-R, 2-4 and OD, in 2nd, 3rd,
and 4th gear 2-4 and OD) are turned on by the
Transmission Control Module (TCM) to see if pump
prime exists. The code is set if none of the pressure
switches respond. The TCM will continue to run the
loss of prime test until pump pressure returns.
Theory of operation:The loss of prime test is
used to prevent transmission defaults which can be
caused by a lack of pump prime.
Transmission Effects:Vehicle will not move or
transmission slips. Normal operation will continue
if pump prime returns.
Possible causes:
> Low transmission fluid level
> PRNDL indicates a valid OD code in the hydrau-
lic reverse position
> Transmission fluid filter clogged or damaged
> Transmission fluid filter improperly installed
(Bolts loose or O-ring missing)
> Oil pump - If a customer has a problem when the
transmission is cold whereby he shifts to reverse,
gets reverse, and then shifts to OD and does not
get OD (gets a neutral condition), and then can
not get reverse or OD for between 3-20 seconds,
replace the oil pump. High side clearance in the
oil pump will set a code 35. The pump will prime
upon start-up, but as the torque converter purges
air (drain down) the air will leak across the inner
rotor into the pump suction port and cause a loss
of prime right after the shift into OD. After 3- 20
seconds, pump prime will return and normal
operation will continue. The pump should be
replaced only after all other possible causes
above have been checked and verified.Name of code:P1790(36) - Fault Immediately
After Shift
When monitored:After a gear ratio error is
stored.
Set condition:This code is set if the associated
gear ratio code is stored within 1.3 seconds after a
shift.
Theory of operation:This code will only be stored
along with a 50 series code. If this code is set, it
indicates the problem is mechanical in nature.
When this code exists, diagnosing the transmission
should be based on the associated gear ratio code
and primarily mechanical causes should be consid-
ered.
Transmission Effects:None
Possible causes:
> Mechanical causes as listed under associated
gear ratio code.
Name of code:P1775(37) - Solenoid Switch Valve
Latched in TCC Position
When monitored:During an attempted shift into
1st gear.
Set condition:This code is set if three unsuccess-
ful attempts are made to get into 1st gear in one
given key start.
Theory of operation:The solenoid switch valve
(SSV) controls the direction of the transmission
fluid when the L-R/TCC solenoid is energized. The
SSV will be in the downshifted position in 1st gear,
thus directing the fluid to the L-R clutch circuit. In
2nd, 3rd, and 4th, it will be in the upshifted position
and directs the fluid into the torque converter
clutch (TCC).
When shifting into 1st gear, a special hydraulic
sequence is performed to ensure SSV movement
into the downshifted position. The L-R pressure
switch is monitored to confirm SSV movement. If
movement is not confirmed (the L-R pressure
switch does not close), 2nd gear is substituted for
1st.
Transmission Effects:Transmission will have no
1st gear (2nd gear will be substituted), and no
EMCC operation.
Possible causes:
> PRNDL indicates a valid OD code in the hydrau-
lic reverse position
> Valve body- - Solenoid valve stuck in TCC posi-
tion
> High idle speed
> Solenoid malfunction - L-R pressure switch will
not close
> L-R Pressure Switch Sense circuit shorted to
battery
10
GENERAL INFORMATION

± Solenoid pack (UD pressure in 4th gear)
Code P0734(54) - Excludes geartrain failures which
should be obvious upon disassembly
> If code P1791(35) is also set, follow diagnostic
procedure for code P1791(35) first
> Failed or slipping OD clutch - may also set code
P0733(53)
± OD and Reverse inner and outer lip seal leak-
age (usually hard code)
± Sticky OD accumulator seals (intermittent)
± Worn reaction shaft support seal rings (hard
code at heavy throttle)
± Broken OD/UD tapered snap ring - (hard code
at heavy throttle)
> Failed or slipping 2-4 clutch - may also set code
P0732(52)
± 2-4 seal leakage (intermittent)
± Sticky accumulator seals (intermittent)
Codes P0715(56) and P0720(57)
> Failed input or output speed sensor (intermittent
or hard code)
> Shorted or open wiring between TCM and speed
sensor(s) (intermittent)
> Connector problems at 60 TCM connector and/or
speed sensor connector
Code P1794(58)
> Open or shorted speed sensor ground (speed
sensor ground is different from chassis ground)
> Open or shorted Temperature Sensor wiring to
TRS
> TRS - Will also set code P1799(74)
> TCM
Name of code:P1796(70) - Autostick Sensor Cir-
cuit (If equipped)
Note: RS is a MUXED Autostick system
When monitored:Whenever the engine is run-
ning.
Set condition:
1) The transmission shift lever is not in AutoStick
and either the upshift or downshift switch is closed.
2) Upshift and downshift switches closed at the
same time.
Theory of operation:In the AutoStick Mode
(manual shift mode), upshifts and downshifts are
actuated manually. Shift requests are detected by
monitoring the MUXED upshift and downshift
switches. The Transmission Control Module (TCM)
monitors the above set conditions. A set condition
will be tolerated for up to 15 seconds before setting
a code.Transmission Effects:The OD position shift
schedule is substituted while operating in the au-
tostick gear selector position. No limp-in mode
occurs.
Possible causes:
> Wiring or connector problems
> AutoStick switch failure
> TCM
Name of code:P1797(71)- Manual Shift Overheat
When monitored:Whenever the engine is run-
ning.
Set condition:1) If the engine temperature ex-
ceeds 124C (255 ÉF) while operating in AutoStick
mode.
2) If the transmission temperature exceeds 135C
(275 ÉF) while in AutoStick mode
Theory of operation:Transmission and engine
temperatures are monitored during vehicle opera-
tion. If conditions occur causing the engine or
transmission to overheat, the AutoStick mode will
be canceled, and a code will be set.
Transmission Effects:The 3 position shift sched-
ule that is used in non-AutoStick applications is
substituted while operating in the AutoStick gear
selector position. No limp-in mode occurs.
Possible causes:
> Engine overheat - refer to service manual for
diagnosis and repair
> Transmission Overheat
± Restricted transmission cooling system
± Transmission fluid overfilled
± Radiator fan not functioning properly
± Extended driving in low gear
Note:Strenuous driving conditions may cause the
vehicle to overheat. If the driver operates in or
initiates AutoStick with an overheated vehicle, the
code will be set.
Name of code:P1798 (73) - Deteriorated Transaxle
Fluid
When monitored:At every Fully Electronically
Modulated Converter Clutch (FEMCC) to Partial
Electronically Modulated Converter Clutch (PEM-
CC) transition miles when A/C compressor clutch is
being cycled.
Set condition:The code will be set if vehicle
shudder is detected 20 times when the A/C clutch is
cycled.
Theory of operation:While in 3rd or 4th gear
FEMCC and just before the A/C clutch engages, the
Powertrain Control Module (PCM) requests the
Transmission Control Module (TCM) to momen-
tarily establish PEMCC operation. If vehicle shud-
der is detected during the FEMCC to PEMCC
transition, a counter is incremented. If the count
reaches 20, the trouble code is set. The driver may
14
GENERAL INFORMATION

then notice harsh bumps when the A/C clutch is
being cycled, but vehicle shudder will be elimi-
nated. After 35 OBDII (EURO STAGE III OBD)
warm-up starts or if the code is cleared, PEMCC
will be reactivated to see if shudder is still present.
If one shudder event occurs, the code will be reset.
Clearing the code and running battery disconnect
with the DRBIIItis the only way to reset the
shudder counter from 20 back to zero.
Transmission Effects:This code does not cause
the transmission to go into limp-in mode. However,
once the code is set, FEMCC to PEMCC operation
before the A/C clutch engagement will be disabled
for 35 OBDII (EURO STAGE III OBD) warm up
starts.
Possible causes:
> Degraded transmission fluid
> Wheels severely out of alignment
> Internal torque converter problem
Name of Code:P1799(74) - Calculated Oil Temper-
ature in Use
When Monitored:When ever the Engine is run-
ning.
Set condition:The code is set if any of the follow-
ing conditions exist for three consecutive key starts:
> The Temperature Sensor voltage is out of range
(below 0.07 volts or greater than 4.94 volts)
> If continuous erratic Temperature Sensor voltage
is sensed.
> The Temperature Sensor temperature stays be-
low 27C (80ÉF) for an extended period of time.
Theory of Operation:The TCM uses a Tempera-
ture Sensor to monitor the transmission sump tem-
perature. This temperature is used to determine
which shift schedule the TCM is to use. (See Trans-
mission Operation and Shift Scheduling at Various
Sump Temperatures in this diagnostic manual) If
the Temperature Sensor circuit fails to operate
properly the TCM will use the calculated oil tem-
perature routine found in prior model year TCM. If
this occurs for three consecutive key starts, the code
will be set. The TCM will then test the Temperature
Sensor circuit after every 35 OBDII (EURO STAGE
III OBD) warm-up starts. If the Temperature Sen-
sor circuit is OK, the Temperature Sensor data is
used in place of the Calculated Oil Temperature
data.
Transmission Effects:If the Temperature Sensor
indicates a temperature below -18C (0É F) or above
115C (240É F) at start up, The TCM compares the
calculated oil temperature to the indicated Temper-
ature Sensor oil temperature. If the calculated oil
temperature differs significantly from the Temper-
ature Sensor value, the calculated oil temperature
will be used for that key start.Possible Causes:
> Wiring or Connector problems in the transmis-
sion temperature sensor signal circuit.
> TRS
> TCM
Name of Code:P1738(75) - High Temperature
Operation Activated.
When Monitored:Whenever the engine is running.
Set Condition:Immediately once the Overheat
Shift Schedule is activated.
Theory of Operation:If the transmission oil tem-
perature rises above 115C (240ÉF), the overheat
shift schedule is activated refer to Transmission
Operation as a function of Transmission Oil Tem-
perature and the code is set. The DTC is an infor-
mation code only and is being set to aid the techni-
cian in determining root cause of a customer
driveability issue. The code is also intended to alert
the technician to determine if a cooling system
malfunction has occurred or if an additional trans-
mission air to oil cooler should be added to the
vehicle if the customer regularly drives in a manner
that overheats the transmission. Extended opera-
tion above 115C (240ÉF) will reduce the durability of
the transmission and should be avoided. Correcting
the cooling system malfunction or installing an
additional transmission oil cooler will improve
transmission durability especially for customers
who operate in city/construction stop and go traffic,
tow trailers regularly, drive aggressively in low gear
or drive regularly in mountainous areas.
Transmission Effects:Information only code. -
Overheat shift schedule was activated, no limp-in
condition occurs. 2nd gear partial EMCC above 40
Km/h (25 MPH), 3rd gear EMCC from 45-69 Km/h
(28-43 MPH), delayed 3-4 upshift at 69 Km/h (43
MPH), early 4-3 coastdown at 66 Km/h (41 MPH),
EMCC operation under all conditions above 40
Km/h (25 MPH) except at closed throttle or 1st gear.
Possible Causes:
± Transmission Overfilled with Oil
± Engine cooling fan failure
± Engine thermostat stuck closed
± Radiator corroded or packed with dirt
± Transmission Oil Cooler Plugged
± Customer driving pattern requires additional
transmission cooling
Name Of Code:P1739(76) - Power-Up at Speed
When Monitored:When TCM (transmission con-
trol module) initially powers-up.
Set Condition:If the TCM powers up while in the
9Drive9position and the vehicle is going above 32
Km/h (20 MPH), the code is set.
Theory of Operation:If a vehicle loses power to
the TCM, the vehicle will go to the 2nd gear mode
15
GENERAL INFORMATION

since there is no power available to control the
transmission solenoids. However if power is re-
stored, the TCM will power-up and normal opera-
tion will be restored. This DTC identifies that
power to the TCM was restored when the gear
selector was in a9Drive9position while the vehicle
was moving at speeds above 32 Km/h (20 MPH). If
a person shifts to Neutral and cycles the ignition
key and quickly shifts to9Drive9while moving
before the TCM comes out of its START ROUTINE,
the DTC can be set. Therefore it is critical that this
DTC diagnosis repair procedure should only be used
if the vehicle is experiencing intermittent 2nd gear
operation and subsequently a return to normal
operation during normal driving.
Transmission Effects:No limp-in condition. The
DTC is for information only when trying to diagno-
sis intermittent 2nd gear operation and subse-
quently a return to normal operation.
Possible Causes:
± No Problem if vehicle is started in9neutral9at
speeds above 32 Km/h (20 MPH) and shifted
quickly to9Drive9before TCM comes out of the
START ROUTINE.
FOR INTERMITTENT 2ND GEAR OPER-
ATION AND THEN A SUBSEQUENT RE-
TURN TO NORMAL OPERATION WITH-
OUT CYCLING THE IGNITION KEY
± Intermittent Direct Battery connection be-
tween TCM (60-way pin 56) and battery.
± Intermittent Fused Ignition Switch Output
between TCM (60-way pin 11) and ignition
switch.
± Intermittent Ground to TCM (60 way pins 53
and 57).
Name of code:P1717(77) - No Communication
with Mechanical Instrument Cluster (MIC)
When monitored:Continuously with key on.
Set condition:If no PCI bus messages are received
from the Mechanical Instrument Cluster (MIC) for
25 seconds.
Theory of operation:The TCM communicates
with the MIC using the PCI bus. It relies on certain
information to function properly. The TCM contin-
uously monitors the PCI bus to check for messages
broadcast from the PCM.
Transmission Effects:Possible improper TCM
AutoStick configuration.
Possible causes:
> Open or shorted PCI bus circuit from MIC
> MIC
> TCM (If other communications codes are stored
in the TCM only)
Name of code:P0600(78) - Serial Communication
Link Malfunction
When monitored:Continuously with key on.
Set condition:If no PCI bus messages are received
by the Transmission Control Module (TCM) for 10
seconds.
Theory of operation:The TCM communicates
with the other modules in the vehicle using the PCI
bus. It relies on certain information to function
properly. The TCM continuously monitors the PCI
bus to check for messages broadcast from the cer-
tain modules.
Transmission Effects:Possible improper TCM
AutoStick configuration and delayed 3-4 shifts. No
EMCC and early 3-4 shifts for a few minutes after
engine is started.
Possible causes:
> Open or shorted PCI bus circuit from BCM
> TCM
Name of code:P1714(79) Low Battery Voltage
When monitored:Continuously with engine run-
ning and Transmission Relay energized.
Set condition:If the voltage sensed at the Trans-
mission Control Relay Output circuit (pins 16 and
17 at TCM) for 15 seconds.
Theory of operation:The Transmission system
requires sufficient battery voltage in order to ener-
gize the transmission solenoids. The TCM continu-
ously monitors the voltage available to the sole-
noids.
Transmission Effects:At speeds above 72 Km/h
(45 MPH) the transmission system will default to
neutral. Below 72 Km/h (45 MPH) the transmission
system will default to relay open limp-in mode.
Park, Reverse, and Neutral are still available.
Possible causes:
> Charging system problem
> Poor/High resistance connection between TCM
and Battery/Alternator
> TCM pin 16 and 17 high resistance or poor
connection
> TCM ground pins 53 and 57 high resistance or
poor connection
> High resistance in Transmission Control Relay
contacts
> TCM
3.3.8 QUICK LEARN
The Quick Learn function customizes adaptive
parameters of the TCM to the transmission charac-
teristics of a vehicle. This gives the customer im-
proved9as received9shift quality compared to the
initial parameters stored in the TCM.
Notes about Quick Learn Features
The nature of the Quick Learn function requires
that certain features must be taken into consider-
ation.
16
GENERAL INFORMATION

> Quick Learn should generally not be used as a
repair procedure unless directed by a repair or
diagnostic procedure. If the transmission system
is exhibiting a problem that you think is caused
by an invalid CVI, you should try to relearn the
value by performing the appropriate driving ma-
neuver. In most cases, if a quick learn makes a
vehicle shift better, the vehicle will return with
the same problem.
> Before performing Quick Learn, it is imperative
that the vehicle be shifted into OD with the
engine running and the oil level set to the correct
level. This step will purge air from the clutch
circuits to prevent erroneous clutch volume val-
ues which could cause poor initial shift quality.
> If an unused TCM is installed on a vehicle with a
HOT engine, Quick Learn will cause the TCM to
report a cold calculated oil temperature. This
requires monitoring the calculated oil tempera-
ture using the DRBIIIt. If the temperature is
below 15C (60É F), the transmission must be run
at idle or driven in gear until it goes above 15C
(60ÉF). If the temperature is above 93C (200ÉF),
the transmission must cool to below 93C (200ÉF).
> First gear is engaged in overdrive after Quick
Learn is completed. Place the vehicle in park
after performing Quick Learn.
The Quick Learn function should be performed:
± Upon installation of a new service TCM
± After replacement or rebuild of internal trans-
mission components or the torque converter
± If one or more of the clutch volumes indexes
(CVI's) contain skewed readings because of
abnormal conditions.
To perform the Quick Learn procedure, the fol-
lowing conditions must be met.
± It is imperative that the vehicle be shifted into
OD with the engine running and the oil level
set to the correct level. This step will purge the
air in the clutch circuits to prevent erroneous
clutch volume values, which could cause poor
initial shift quality.
± The brakes must be applied.
± The engine must be idling.
± The throttle angle (TP sensor) must be less
than 3 degrees.
± The shift lever position must stay in neutral
until prompted to shift into OD.
± The shift lever must stay in OD after the9Shift
to Overdrive9prompt until the DRBIIItindi-
cates the procedure is complete.
± The oil temperature must be between 15C
(60ÉF) and 93C (200ÉF).NOTE:The above conditions must be maintained
during the procedure to keep the procedure from
being aborted.
The Quick Learn procedure is performed with the
DRBIIItby selecting9Transmission9system then
9Miscellaneous9functions, then9Quick Learn9. Follow
the procedure instructions displayed on the DRBIIIt.
3.3.9 CLUTCH VOLUMES
The L-R clutch volume is updated when doing a
2-1 or 3-1 coast down shift. The transmission tem-
perature must be between 21-49C (70-120É F). The
clutch volume should be between 35 and 83.
The 2-4 clutch volume is updated when doing a
1-2 shift. The transmission temperature must be
above 43C (110ÉF). The clutch volume should be
between 20 and 77.
The OD clutch volume is updated when doing a
2-3 shift. The transmission temperature must be
above 43C (110ÉF). The clutch volume should be
between 40 and 150.
The UD clutch volume is updated when doing a
4-3 or 4-2 shift. The transmission temperature must
be above 43C (110ÉF). The clutch volume should be
between 24 and 70.
3.3.10 ELECTRONIC PINION FACTOR
The transmission output speed signal supplies
distance pulses to the powertrain control module
(PCM), which are used to calculate speed and
mileage. A pinion factor is stored in the transmis-
sion control module (TCM) in order to provide the
appropriate distance pulses for the vehicle. The
pinion factor is programmed into the TCM at the
assembly plant.
Using the following steps, the pinion factor can be
checked and/or reset using the DRBIIIt:
1. Select Transmission system, then Miscellaneous
functions, then Pinion Factor. The DRBIIItwill
display the current tire size.
2. If the tire size is incorrect, depress the Enter key
and then select the correct size.
3. Depress the Page Back key to exit the reset
procedure.
Notes About Electronic Pinion Factor Features
The nature of the electronic pinion factor requires that
certain features must be taken into consideration.
> If no pinion factor is stored in an installed TCM,
the vehicle speedometer will not operate, engine
speed will be limited to 2300 RPM, and catalyst
damage may occur.
> Selecting a wrong tire size will cause the speed-
ometer to be inaccurate and will also cause any
speed related features to operate improperly.
Note: After replacing the TCM, you must
reprogram pinion factor
17
GENERAL INFORMATION