Chrysler PT Cruiser 2001 Service Manual Supplement page 2761

Name of code: 70 - Autostick Input Circuit
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 switches are
closed.
2. Both the upshift and downshift switches are
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 upshift and downshift switches. The
Transmission Control Module (TCM) monitors the
above set conditions. A set condition will be toler-
ated 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:
> Wirng or connector problems
> AutoStick switch failure
> Defective TCM
Name of code: P-1797(71) — Manual Shift Over-
heat
When monitored: Whenever the engine is run-
ning.
Set condition:
1. If the engine temperatures exceeds 255°F while
operating in AutoStick mode.
2. If the transmission temperature exceeds 275°F
while in AutoStick mode
Theory of operation: Transmission and engine
temperatures are monitored during vehicle opera-
tion. If conditions occur causing the engine or
transmision to overheat, the AutoStick mode will be
canceled, and a code will be set.
Transmission Effects: The ''3'' position shift
schedule that is used in non-AutoStick applications
is substitued 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.
GENERAL INFORMATION
Name of code: P-1798(73) — Deteriorated Tran-
saxle Fluid
When monitored: At every Fully Electronically
Modulated Converter Clutch (FEMCC) to Partial
Electronically Modulated Converter Clutch (PEM-
CC) transmission 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 or PEMCC
transition, a counter is incremented. If the count
reaches 20, the trouble code is set. The driver may
then notice harsh bumps when the A/C clutch is
being cycled, but vehicle shudder will be elimi-
nated. After 35 OBDII warm-ups starts or if the
code is cleared, PEMCC will be reactivated to see if
shudder is still present. If one shudder event oc-
curs, the code will be reset. Clearing the code and
running battery with the DRBIII is 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 warm up starts.
Possible causes:
> Degraded transmission fluid
> Wheels severely out of alignment
> Internal torque converter problem
Name of code: P-1799(74) — Calculated Oil Tem-
perature in Use
When monitored: Whenever 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 Transmission Temperature Sensor voltage is
out of range (below 0.07 volts or greater than 4.94
volts)
> If continuous erratic Transmission Temperature
Sensor voltage is sensed.
> The Transmission Temperature Sensor tempera-
ture stays below 80°F for an extended period of
time.
Theory of operation: The TCM uses a Transmis-
sion Temperature Sensor to monitor the transmis-
sion's sump temperature. This temperature is used
to determine which shift schedule the TCM is to
use. (See ''Transmission Operation and Shift Sched-
uling at Various Sump Temperatures'' section 3.2.2
of this diagnostic manual.) If Transmission Temper-
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