Chrysler PT Cruiser 2001 Service Manual Supplement page 2763

– Intermittent Ground to TCM (60-way pins 53
and 57).
Name of code: P-0717(77) — No Communication
with Mechanical Instrument Cluster (MIC)
When monitored: Continuously with key on.
Set condition: If no PCI bus messages are re-
ceived 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 to PCI bus circuit from MIC
> MIC
> TCM (If other communication codes are stored in
TCM only)
Name of code: P-0600(78) — Serial Communica-
tion Link Malfunction
When monitored: Continuously with key on.
Set condition: If no PCI bus messages are re-
ceived 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 certain
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: P-1714(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 circuits (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 45 MPH,
the transmission system will default to neutral.
Below 45 MPH, the transmission system will de-
GENERAL INFORMATION
fault to relay open limp-in mode. Park, Reverse,
Neutral are still available.
Possible causes:
> Charging system problem
> Poor/High resistance connection between TCM
and Battery/Alternator
> TCM pins 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-
proved ''as received'' shift 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.
> 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 re-learn the
value by performing the appropriate maneuver
as described in section 3.3.9. 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 DRBIII . If the temperature is
below 60°F, the transmission must be at idle or
driven in gear until it goes above 60°F. If the
temperature is above 200°F, the transmission
must cool to below 200°F.
> 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
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