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
4.3 WARNINGS
4.3.1 VEHICLE DAMAGE WARNINGS
Before disconnecting any control module, make
sure the ignition is ªoffº. Failure to do so could
damage the module.
When testing voltage or continuity at any control
module, use the terminal side (not the wire end) of
the connector. Do not probe a wire through the
insulation; this will damage it and eventually cause
it to fail because of corrosion.
Be careful when performing electrical tests so as
to prevent accidental shorting of terminals. Such
mistakes can damage fuses or components. Also, a
second code could be set, making diagnosis of the
original problem more difficult.
4.3.2 ROAD TEST COMPLAINT VEHICLE
Some complaints will require a test drive as part
of the repair verification procedure. The purpose of
the test drive is to try to duplicate the diagnostic
code or symptom condition.
CAUTION: BEFORE ROAD TESTING A
VEHICLE, BE SURE THAT ALL
COMPONENTS ARE REASSEMBLED.
DURING THE TEST DRIVE, DO NOT TRY TO
READ THE DRBIIITSCREEN WHILE IN
MOTION. DO NOT HANG THE DRBIIITFROM
THE REAR VIEW MIRROR OR OPERATE IT
YOURSELF. HAVE AN ASSISTANT
AVAILABLE TO OPERATE THE DRBIIIT.
Road testing is an essential step in the diagnostic
process that must not be overlooked. Along with
diagnostic information obtained from the DRBIIIt
Scan Tool and the original customer concern, the
road test helps to verify the problem and observe
operation under actual vehicle driving conditions.
Just as important as the road test is, there are
preliminary inspections that should be carried out
prior to the road test. Always check the fluid level
and condition before going on a road test or per-
forming other tests. Also try to determine the type
of fluid being used. Improper fluid can result in
problems. Additionally, a variety of complaints can
be caused by incorrect fluid level. Some of the
conditions caused by incorrect fluid level are as
follows:
²Delayed engagement
²Poor shifting or erratic shifts
²Excessive noise
²Overheating
The next step is to verify that the shift linkage is
correctly adjusted. If the gearshift linkage is incor-rectly adjusted because of wear or incorrect adjust-
ment, a number of complaints can result.
The TCM monitors the Shift Lever Position (SLP)
Sensor at all times. If the linkage is incorrectly
adjusted, the TCM may sense a shift lever position
that is not correct for the gear range chosen by the
driver. This may cause diagnostic trouble codes to
be set and a possible limp-in situation.
The following complaints may also be the result
of an incorrectly adjusted or worn linkage.
²Delayed clutch engagement or erratic shifts
²Vehicle able to drive in Neutral
²Engine not able to crank in Park or Neutral
²Gearshift linkage able to be shifted without the
key in the ignition
²Not able to remove the ignition key in Reverse
²Parking pawl not engaging
The shift linkage should also be adjusted when
replacing the transaxle, repairing the valve body or
repairing any component between the shift lever
and the transaxle.
Some questions to ask yourself when considering
the road test are listed below:
²Is the complaint or concern what you think it is,
based the driver 's description of the problem?
²Is the transaxle operating normally, or is there a
real problem?
²When does the malfunction occur?
²Is the problem in only one gear range?
²What temperature does the complaint occur?
²Is the transaxle in limp-in mode?
4.3.3 ELECTRONIC PINION FACTOR
WARNINGS
The pinion factor must be set for all new trans-
mission control modules. If the pinion factor is not
set or if it is set incorrectly, any speedometer, speed
control, rolling door locks, and other devices that
are operated by the powertrain and body controllers
will not function properly.
4.3.4 BULLETINS AND RECALLS
The service procedures contained in this manual
are correct. provided that all applicable Safety
Recalls and Technical Service Bulletins have been
performed.
5.0 REQUIRED TOOLS AND
EQUIPMENT
> DRBIIIt(diagnostic read-out box) - Must be at
latest release level.
20
GENERAL INFORMATION
Symptom:
P0120-THROTTLE POSITION SENSOR SIGNAL CIRCUIT
When Monitored and Set Condition:
P0120-THROTTLE POSITION SENSOR SIGNAL CIRCUIT
When Monitored: Whenever the engine is running.
Set Condition: This code is set if the throttle angle goes out of range or if throttle angle
changes abruptly (i.e.: faster than the throttle body motion could occur).
POSSIBLE CAUSES
RELATED PCM DTC'S PRESENT
INTERMITTENT WIRING & CONNECTORS
SENSOR GROUND CIRCUIT OPEN TO TCM
TPS SIGNAL CIRCUIT OPEN TO TCM
TPS VOLTAGE CHANGE NOT SMOOTH
TCM - TPS SIGNAL CIRCUIT
TEST ACTION APPLICABILITY
1NOTE: Low fluid level can be the cause of many Transmission problems. If
the fluid level is low locate and repair the leak then check and adjust the
fluid level per the Service Information.
NOTE: Always perform diagnostics with a fully charged battery to avoid
false symptoms.
With the DRBIIIt, read the engine DTC's. Check and repair all engine DTC's prior
to performing Transmission Symptom Diagnostics.
With the DRBIIIt, read Transmission DTC's. Record all DTC's and 1 Trip Failures.
NOTE: Diagnose 1 Trip Failures as a fully matured DTC.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
Repair as necessary.
Perform the Shift Lever Position Test. If the test does not pass, refer to Symptom test
for P0705 Check Shifter Signal.
For Gear Ratio DTC's, check and record all CVI's.
Most DTC's set on start up but some must be set by driving the vehicle such that all
diagnostic monitors have run.
NOTE: Verify flash level of Transmission Control Module. Some problems
are corrected by software upgrades to the Transmission Control Module.
NOTE: Check for applicable TSB's related to the symptom.
Perform this procedure prior to Symptom diagnosis.All
Continue
Go To 2
2 With the DRBIIIt, check Powertrain Control Module DTC's.
Are any of the following P-codes P0122, P0123, P0121 stored in the PCM?All
Ye s®Refer to the Driveability category for the related symptom(s).
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
No®Go To 3
24
TRANSMISSION
TEST ACTION APPLICABILITY
3 Start the engine. Allow the engine to idle.
With the DRBIIIt, Check the Throttle Position Sensor Voltage under Transmission
Sensors.
Is the Throttle Position Sensor voltage below 0.3 or above 1.0 volts?All
Ye s®Go To 4
No®Go To 7
4 Turn the ignition off.
Disconnect the TPS harness connector.
Disconnect the TCM harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance of the Sensor Ground circuit between the TPS harness
connector and the Transmission Control Module harness connector.
Is the resistance below 5.0 ohms?All
Ye s®Go To 5
No®Repair the Sensor Ground circuit for an open.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
5 Turn the ignition off.
Disconnect the Throttle Position Sensor harness connector.
Disconnect the Transmission Control Module harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance of the TPS Signal Circuit from the TCM harness connector to
the TPS harness connector.
Is the resistance below 5.0 ohms?All
Ye s®Go To 6
No®Repair the TPS signal circuit for an open.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
6 If there are no possible causes remaining, view repair. All
Repair
Replace the TCM. WITH THE DRBIIItPERFORM QUICK
LEARN AND REPROGRAM PINION FACTOR.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
7 The conditions necessary to set this DTC are not present at this time. Using the
schematics as a guide, inspect the wiring and connectors specific to this circuit.
Wiggle the wires while checking for shorts and open circuits.
Pay particular attention to the the point where the TPS signal and sensor ground
circuits splice off from the engine circuits.
Were any problems found?All
Ye s®Repair wiring and/or connector as necessary.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
No®Go To 8
8 Turn the ignition on.
With the DRBIIIt, read TPS VOLTS.
While monitoring the DRBIIIt, slowly open and close the Throttle.
Is the voltage change smooth?All
Ye s®Test Complete.
No®Replace the Throttle Position Sensor.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
25
TRANSMISSION
P0120-THROTTLE POSITION SENSOR SIGNAL CIRCUIT ÐContinued
TEST ACTION APPLICABILITY
1NOTE: Low fluid level can be the cause of many Transmission problems. If
the fluid level is low locate and repair the leak then check and adjust the
fluid level per the Service Information.
NOTE: Always perform diagnostics with a fully charged battery to avoid
false symptoms.
With the DRBIIIt, read the engine DTC's. Check and repair all engine DTC's prior
to performing Transmission Symptom Diagnostics.
With the DRBIIIt, read Transmission DTC's. Record all DTC's and 1 Trip Failures.
NOTE: Diagnose 1 Trip Failures as a fully matured DTC.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
Repair as necessary.
Perform the Shift Lever Position Test. If the test does not pass, refer to Symptom test
for P0705 Check Shifter Signal.
For Gear Ratio DTC's, check and record all CVI's.
Most DTC's set on start up but some must be set by driving the vehicle such that all
diagnostic monitors have run.
NOTE: Verify flash level of Transmission Control Module. Some problems
are corrected by software upgrades to the Transmission Control Module.
NOTE: Check for applicable TSB's related to the symptom.
Perform this procedure prior to Symptom diagnosis.All
Continue
Go To 2
2 Using the DRBIIIt, perform the Shift Lever Position Test.
Select the test outcome from the following:All
Test passes
Go To 3
Test fails with DTC
Go To 4
Test fails without DTC
Adjust the shift linkage per the Service Information.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
3 The conditions necessary to set this DTC are not present at this time.
Using the schematics as a guide, inspect the wiring and connectors specific to this
circuit.
Wiggle the wiring while checking for shorts and open circuits.
Were there any problems found?All
Ye s®Repair as necessary.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
No®Test Complete.
32
TRANSMISSION
P0705-CHECK SHIFTER SIGNAL ÐContinued
TEST ACTION APPLICABILITY
4 Turn the ignition off to the lock position.
CAUTION: Remove the Starter Relay from the IPM. This will prevent the
vehicle from being started in gear.
Install Transmission Simulator, Miller tool #8333 and the FWD Adapter Cable kit,
Miller tool #8333-1.
Ignition on, engine not running.
With the DRBIIIt, perform the Shift Lever Position Test with the Transmission
Simulator installed.
When the DRBIIItinstructs you to put the Gear Selector in a particular position,
you must do so using the Simulator tool. The LED for the gear position in question
must be illuminated prior to hitting9enter9on the DRBIIIt.
Did the test pass?All
Ye s®Go To 5
No®Go To 6
NOTE: Disconnect the Transmission Simulator and reconnect all the har-
ness connectors.
5 If there are no possible causes remaining, view repair. All
Repair
Replace the Transmission Range Sensor.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
6 Ignition on, engine not running.
With the DRBIIItin Inputs/Outputs, read the TRS Sense circuits C1 thru C4.
Move the shift lever thru all gear positions, pausing momentarily in each gear
position. Watch for one of the circuits to not change state.
Pick the one that did not change state.All
TRS T1 sense (C4)
Go To 7
TRS T3 sense (C3)
Go To 11
TRS T41 sense (C1)
Go To 15
TRS T42 sense (C2)
Go To 19
7 Turn the ignition off to the lock position.
Disconnect the TRS harness connector.
Disconnect the TCM harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance of the TRS T1 Sense circuit from the TCM harness connector
to the TRS harness connector.
Is the resistance above 5.0 ohms?All
Ye s®Repair the TRS T1 Sense circuit for an open.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
No®Go To 8
33
TRANSMISSION
P0705-CHECK SHIFTER SIGNAL ÐContinued
TEST ACTION APPLICABILITY
8 Turn the ignition off to the lock position.
Disconnect the TRS harness connector.
Disconnect the TCM harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance between the TRS T1 Sense circuit at the TCM connector and
ground.
Is the resistance below 5.0 ohms?All
Ye s®Repair the TRS T1 Sense circuit for a short to ground.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
No®Go To 9
9 Turn the ignition off to the lock position.
Disconnect the TRS harness connector.
Disconnect the TCM harness connector.
Remove the Transmission Control Relay from the IPM.
Note: Check connectors - Clean/repair as necessary.
Connect a jumper wire between the Fused B+ circuit and the Transmission Control
Relay Output circuit in the Transmission Control Relay connector in the IPM.
Ignition on, engine not running.
Measure the voltage of the TRS T1 Sense circuit at the TCM harness connector.
Is the voltage above 0.5 volt?All
Ye s®Repair the TRS T1 Sense circuit for a short to voltage.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
No®Go To 10
10 If there are no possible causes remaining, view repair. All
Repair
Replace the TCM. WITH THE DRBIIItPERFORM QUICK
LEARN AND REPROGRAM PINION FACTOR.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
11 Turn the ignition off to the lock position.
Disconnect the TRS harness connector.
Disconnect the TCM harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance of the TRS T3 Sense circuit from the TCM harness connector
to the TRS harness connector.
Is the resistance above 5.0 ohms?All
Ye s®Repair the TRS T3 Sense circuit for an open.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
No®Go To 12
12 Turn the ignition off to the lock position.
Disconnect the TRS harness connector.
Disconnect the TCM harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance between ground and the TRS T3 Sense circuit in the TCM
harness connector.
Is the resistance below 5.0 ohms?All
Ye s®Repair the TRS T3 Sense circuit for a short to ground.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
No®Go To 13
34
TRANSMISSION
P0705-CHECK SHIFTER SIGNAL ÐContinued