
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

3.4 USING THE DRBIIIT
Refer to the DRBIIItusers guide for instructions
and assistance with reading trouble codes, erasing
trouble codes, and other DRBIIItfunctions.
3.5 DRBIIITERROR MESSAGES
Under normal operation, the DRBIIItwill dis-
play one of only two error messages:
± User-Requested WARM Boot
± User-Requested COLD Boot
If the DRBIIItshould display any other error
message, record the entire display and call the
S.T.A.R.. Center. This is a sample of such an error
message display:
ver: 2.14
date: 26 Jul93
file: key_itf.cc
date: Jul 26 1993
line: 548
err: 0x1
User-Requested COLD Boot
Press MORE to switch between this
display and the application screen.
Press F4 when done noting information.
3.5.1 DRBIIITDOES NOT POWER UP
(BLANK SCREEN)
If the LED's do not light or no sound is emitted at
start up, check for loose cable connections or a bad
cable. Check the vehicle battery voltage. A mini-
mum of 11 volts is required to adequately power the
DRBIIIt.
If all connections are proper between the DRBIIIt
and the vehicle or other devices, and the vehicle
battery is fully charged, an inoperative DRBIIIt
may be the result of faulty cable or vehicle wiring.
For a blank screen, refer to the appropriate Body
Diagnostic manual.
3.5.2 DISPLAY IS NOT VISIBLE
Low temperatures will affect the visibility of the
display. Adjust the contrast to compensate for this
condition.
3.6 TRANSMISSION SIMULATOR
(MILLER TOOL # 8333) AND FWD
ADAPTER (MILLER TOOL #8333-1)
The transmission simulator, simply put, is an
electronic device that simulates the electronic func-
tions of any EATX controlled transmission (41TE,
42LE, 45RFE, and 545RFE). It's basic function is toaid the technician in determining if an internal
transmission problem exists or if the problem re-
sides in the vehicle wiring or Transmission Control
Module (TCM). It is only useful for electrical prob-
lems. It will not aid in the diagnosis of a failed
mechanical component, but it can tell you that the
TCM and wiring are working properly and that the
problem is internal.
The ignition switch should be in the lock position
before attempting to install the simulator. Follow
all instructions included with the simulator. If the
feedback from the simulator is in doubt, you can
verify it's operation by installing it on a known good
vehicle. A9known good vehicle9would be defined as
a vehicle that does not set any DTC's and drives and
shifts as expected.
One important point to remember is that the
Simulator receives it's power from the Trans Relay
Output circuit. If the transmission system is in
Limp-in (Relay open), the simulator will not oper-
ate. This is not really an indication of a problem,
but an additional symptom. If the simulator does
not power up (9P9led lit), this is an indication that
the problem is still present with the simulator
hooked up. This indicates that the problem is in the
wiring or TCM and not the transmission.
Miller Tool # 8333-1 consists of the adapter cables
and overlay necessary to adapt the simulator to
41TE and 42LE transmissions.
4.0 DISCLAIMERS, SAFETY,
AND WARNINGS
4.1 DISCLAIMERS
All information, illustrations and specifications
contained in this manual are based on the latest
18
GENERAL INFORMATION

Symptom:
P1765-SWITCHED BATTERY
When Monitored and Set Condition:
P1765-SWITCHED BATTERY
When Monitored: Ignition key is turned from the OFF position to RUN position and/or
ignition key is turned from the CRANK position to RUN position.
Set Condition: This DTC is set if the Transmission Control Module senses voltage on any
of the Pressure Switch Inputs prior to the TCM energizing the Transmission Control Relay.
POSSIBLE CAUSES
INTERMITTENT WIRING AND CONNECTORS
2-4 PRESSURE SWITCH SENSE CIRCUIT SHORT TO VOLTAGE
L/R PRESSURE SWITCH SENSE CIRCUIT SHORT TO VOLTAGE
OD PRESSURE SWITCH SENSE CIRCUIT SHORT TO VOLTAGE
TCM - SWITCHED BATTERY
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 the STARTS SINCE SET counter.
Note: This counter only applies to the last DTC set.
Is the STARTS SINCE SET counter for P1765 set at 0?All
Ye s®Go To 3
No®Go To 7
86
TRANSMISSION

Symptom:
P1767-TRANSMISSION RELAY ALWAYS ON
When Monitored and Set Condition:
P1767-TRANSMISSION RELAY ALWAYS ON
When Monitored: When ignition key is turned from the OFF position to the RUN position
and/or ignition is turned from the CRANK position to RUN position.
Set Condition: This DTC is set if the Transmission Control Module senses greater than
3 volts at the Transmission Control Relay Output terminal of the TCM prior to the TCM
energizing the relay.
POSSIBLE CAUSES
INTERMITTENT WIRING AND CONNECTORS
TRANSMISSION CONTROL RELAY STUCK CLOSED
TRANSMISSION CONTROL RELAY OUTPUT CIRCUIT SHORT TO VOLTAGE
TRANSMISSION RELAY CONTROL CIRCUIT SHORT TO VOLTAGE
TCM - TRANSMISSION RELAY ALWAYS ON
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
89
TRANSMISSION

Symptom:
P1792-BATTERY WAS DISCONNECTED
When Monitored and Set Condition:
P1792-BATTERY WAS DISCONNECTED
When Monitored: Whenever the key is in the Run/Start position.
Set Condition: This code is set whenever Transmission Control Module (TCM) is
disconnected from battery power B+ or ground. It will also be set during the DRBIIIt
Quick Battery Disconnect procedure.
POSSIBLE CAUSES
QUICK LEARN WAS PERFORMED
RECENT BATTERY DISCONNECTION
TCM WAS REPLACED OR DISCONNECTED
INTERMITTENT WIRING AND CONNECTORS
FUSED B+ CIRCUIT TO TCM OPEN
GROUND CIRCUIT OPEN
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
127
TRANSMISSION

Symptom:
P1799-CALCULATED OIL TEMP IN USE
When Monitored and Set Condition:
P1799-CALCULATED OIL TEMP IN USE
When Monitored: Whenever the engine is running. The code is set if any of the following
conditions exist for three consecutive key starts: The thermistor voltage is out of range
(below 0.70 volts or greater than 4.94 volts)
Set Condition: If continuos erratic thermistor voltage is sensed. The thermistor temper-
ature stays below 80 degree's Fahrenheit for an extended period time.
POSSIBLE CAUSES
INTERMITTENT WIRING AND CONNECTORS
SPEED SENSOR GROUND CIRCUIT OPEN
TRANSMISSION TEMPERATURE SENSOR SIGNAL CIRCUIT OPEN
TRANSMISSION TEMPERATURE SENSOR SIGNAL CIRCUIT SHORT TO GROUND
SPEED SENSOR GROUND CIRCUIT SHORT TO VOLTAGE
TRANSMISSION TEMPERATURE SENSOR SIGNAL CIRCUIT SHORT TO VOLTAGE
TRANSMISSION TEMPERATURE SENSOR INOPERATIVE
TCM - HI TRANSMISSION TEMPERATURE SENSOR
TCM - LO TRANSMISSION TEMPERATURE SENSOR
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
142
TRANSMISSION