MERCEDES-BENZ SPRINTER 2006 Service Manual

Dealer Technical Operations
800 Chrysler Drive
CIMS 486-02-76
Auburn Hills, MI 48326-2757

TABLE OF CONTENTS
1.0 INTRODUCTION.........................................................1
1.1SYSTEM COVERAGE...............................................1
1.2SIX -STEP TROUBLESHOOTING PROCEDURE..........................1
2.0 IDENTIFICATION OF SYSTEM.............................................1
3.0 SYSTEM DESCRIPTION AND FUNCTIONAL OPERATION......................1
3.1GENERAL DESCRIPTION............................................1
3.2FUNCTIONAL OPERATION...........................................1
3.2.1CONTROLLER MODES OF OPERATION........................2
3.2.2MIL ILLUMINATION..........................................2
3.2.3SOLENOIDS...............................................2
3.2.4TRANSMISSION COMPONENT DESCRIPTIONS.................3
3.2.5TRANSMISSION OPERATION AND SHIFT SCHEDULING..........4
3.2.6TRANSMISSION ADAPTIVES - INITIALIZE AND STORE...........4
3.3DIAGNOSTIC TROUBLE CODES......................................4
3.3.1ACTIVE (HARD) CODE......................................4
3.3.2STORED (INTERMITTENT) CODE.............................4
3.3.3TROUBLE CODE ERASURE..................................5
3.4USING THE DRBIIIT.................................................5
3.5DRBIIITERROR MESSAGES.........................................5
3.5.1DRBIIITDOES NOT POWER UP (BLANK SCREEN)...............5
3.5.2DISPLAY IS NOT VISIBLE....................................5
4.0 DISCLAIMERS, SAFETY, AND WARNINGS..................................5
4.1DISCLAIMERS......................................................5
4.2SAFETY...........................................................6
4.2.1TECHNICIAN SAFETY INFORMATION..........................6
4.2.2VEHICLE PREPARATION FOR TESTING........................6
4.2.3SERVICING SUB-ASSEMBLIES...............................6
4.2.4DRBIIITSAFETY INFORMATION...............................6
4.3WARNINGS........................................................7
4.3.1VEHICLE DAMAGE WARNINGS...............................7
4.3.2ROAD TESTING A COMPLAINT VEHICLE.......................7
4.4.4BULLETINS AND RECALLS...................................7
5.0 REQUIRED TOOLS AND EQUIPMENT......................................8
6.0 GLOSSARY OF TERMS...................................................8
6.1ACRONYMS.......................................................8
6.2DEFINITIONS......................................................8
7.0 DIAGNOSTIC INFORMATION AND PROCEDURES............................9
COMMUNICATION
*NO RESPONSE FROM SHIFTER ASSEMBLY...............................10
*NO RESPONSE FROM TRANSMISSION CONTROL MODULE.................12
SHIFT LEVER ASSEMBLY
BACKUP LAMP CKT SHORT TO GROUND..................................14
i

TABLE OF CONTENTS - Continued
BACKUP LAMP CKT SHORT TO VOLTAGE OR OPEN........................15
BACKUP LAMP SUPPLY CIRCUIT OPEN...................................16
CAN BUS CIRCUIT......................................................17
INCORRECT CAN MESSAGE FROM ABS...................................18
INTERNAL CONTROLLER................................................19
LR WHEEL SPIN CAN MESSAGE NOT VALID...............................20
OVER VOLTAGE........................................................21
RR WHEEL SPIN CAN MESSAGE NOT VALID...............................22
UNDER VOLTAGE......................................................23
TRANSMISSION - NAG1
1-2/4-5 SOLENOID CIRCUIT..............................................24
1-2/4-5 SOLENOID CIRCUIT SHORT TO GROUND...........................24
2-3 SOLENOID CIRCUIT.................................................27
2-3 SOLENOID CIRCUIT SHORT TO GROUND..............................27
3-4 SOLENOID CIRCUIT.................................................30
3-4 SOLENOID CIRCUIT SHORT TO GROUND..............................30
ABS BRAKE MESSAGE..................................................33
ABS CAN MESSAGE INCORRECT.........................................35
ABS CAN MESSAGE MISSING............................................36
ABS LF SENSOR MESSAGE..............................................38
ABS LR SENSOR MESSAGE.............................................40
ABS RF SENSOR MESSAGE.............................................42
ABS RR SENSOR MESSAGE.............................................44
ACCEL PEDAL SENSOR CAN MESSAGE INCORRECT.......................46
CAN BUS CIRCUIT......................................................48
CAN MESSAGE FROM ECM FROM SLA....................................53
CONTROL MODULE TCM IS NOT CODED..................................55
ENGINE CAN MESSAGE INCORRECT.....................................56
ENGINE CAN MESSAGE MISSING........................................58
ENGINE OVERSPEED...................................................60
ENGINE RPM MESSAGE.................................................62
ENGINE TEMP MESSAGE................................................64
ENGINE TORQUE MESSAGE INCORRECT.................................66
ENGINE TORQUE REDUCTION...........................................68
IC CAN MESSAGE INCORRECT..........................................70
IC/ATC CAN MESSAGE MISSING..........................................72
IMPROPER GEAR......................................................74
IMPROPER RATIO......................................................76
INPUT SENSOR MISMATCH..............................................78
INPUT SENSOR OVERSPEED............................................80
INTERNAL CONTROLLER................................................82
INVALID CONTROL MODULE VERSION....................................83
MODULATING PRESSURE SOLENOID CIRCUIT.............................84
N2 INPUT SPEED SENSOR CIRCUIT......................................87
N3 INPUT SPEED SENSOR CIRCUIT......................................91
SENSOR SUPPLY VOLTAGE..............................................95
SHIFT LEVER POSITION INVALID.........................................97
SHIFT PRESSURE SOLENOID CIRCUIT....................................99
SLA CAN MESSAGE INCORRECT........................................102
SOLENOID SUPPLY VOLTAGE...........................................103
SOLENOID SUPPLY/WATCHDOG.........................................105
SYSTEM OVERVOLTAGE...............................................107
ii

TABLE OF CONTENTS - Continued
SYSTEM UNDERVOLTAGE..............................................109
TCC OVER TEMP......................................................111
TCC SOLENOID CIRCUIT...............................................112
TCC STUCK ON.......................................................115
TRANS TEMP SENSOR - P/N SWITCH CIRCUIT............................117
TRANS TEMP SENSOR ERRATIC........................................120
TRANS TEMP SENSOR SHORTED.......................................122
TRANSMISSION SLIPPING..............................................125
VERIFICATION TESTS
VERIFICATION TESTS..................................................127
8.0 COMPONENT LOCATIONS..............................................129
8.1ENGINE CONTROL MODULE.......................................129
8.2TRANSMISSION CONTROL MODULE................................129
8.3TRANSMISSION SOLENOID ASSEMBLY..............................129
9.0 CONNECTOR PINOUTS................................................131
ELECTROHYDRAULIC CONTROL UNIT - BLACK...........................131
SHIFTER ASSEMBLY - BLACK...........................................131
TRANSMISSION CONTROL MODULE C1 - BLACK..........................131
TRANSMISSION CONTROL MODULE C2 - BLACK..........................132
TRANSMISSION RELAY (RELAY BLOCK)..................................133
10.0 SCHEMATIC DIAGRAMS................................................135
11.0 CHARTS AND GRAPHS................................................137
11.15 VOLT SQUARE WAVE ± TYPICAL PATTERN.........................137
11.2TRANSMISSION TEMP SENSOR....................................138
iii

NOTES
iv

1.0 INTRODUCTION
The procedures contained in this manual include
all of the specifications, instructions, and graphics
needed to diagnose NAG1 Electronic Automatic
Transmission and Shift Lever Assembly problems.
The diagnostics in this manual are based on the
failure condition or symptom being present at the
time of diagnosis.
When repairs are required, refer to the appropri-
ate volume of the service information for the proper
removal and repair procedure.
READ THIS MANUAL BEFORE TRYING TO
DIAGNOSE A VEHICLE TROUBLE CODE.
Diagnostic procedures change every year. New
diagnostic systems may be added and/or carryover
systems may be enhanced. It is recommended that
you review the entire manual to become familiar
with all new and changed diagnostic procedures.
1.1 SYSTEM COVERAGE
This diagnostic procedures manual covers all
Sprinter (VA) equipped with a NAG1 Automatic
Transmission.
1.2 SIX -STEP TROUBLESHOOTING
PROCEDURE
Diagnosis of the NAG1 electronic transmission 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
The NAG1 Transmission family can be identified
by the presence of a 13 pin electrical connector, with
a bayonet lock on the right hand side of the trans-
mission. The connector is oriented horizontally.
3.0 SYSTEM DESCRIPTION AND
FUNCTIONAL OPERATION
3.1 GENERAL DESCRIPTION
The NAG1 electronic transmission is an electron-
ically controlled five speed transmission with a
controlled slip torque converter. The NAG1 elec-tronic transmission is a conventional transmission
in that it uses hydraulically applied clutches to shift
a planetary gear train. However, the electronic
control system replaces many of the mechanical and
hydraulic components used in conventional trans-
mission valve bodies.
The ratios for the gear stages are obtained by 3
planetary gear sets. Fifth Gear is designed as an
Overdrive with a high speed ratio. The gears are
actuated electronically/hydraulically. The electronic
control system enables precise adaptation of pres-
sures to the respective operating conditions and to
the engine output during a shift phase, which
results in a significant improvement in shift qual-
ity.
3.2 FUNCTIONAL OPERATION
The NAG1 electronic transmission has a fully
adaptive control system. The system performs its
functions based on continuous real-time sensor and
switch feedback information. In addition the TCM
receives information from the Shift Lever Assembly,
ECM (engine management) and ABS (chassis sys-
tems) controllers over the CAN bus. The CAN bus is
a high speed communication bus that allows real
time control capability between various controllers.
Most messages are sent every 20 milliseconds, this
means critical information can be shared between
the Transmission, Shifter, Engine and ABS control-
lers. The CAN bus is a two wire bus with aCAN C
Bus (+) circuitand aCAN C Bus (-) circuit. The
CAN bus uses a twisted pair of wires in the harness
to reduce the potential of radio and noise interfer-
ence. The CAN bus also uses a 120 ohm terminating
resistor in both the ECM and Sentry Key Remote
Entry Module (SKREEM) modules. The module
terminating resistance is measured across both
CAN bus circuits at the ECM or SKREEM module.
The control system automatically adapts to
changes in engine performance, vehicle speed, and
transmission temperature variations to provide
consistent shift quality. The control system ensures
that clutch operation during upshifting and down-
shifting is more responsive without increased
harshness. The TCM controls the actuation of sole-
noid valves for modulating shift pressure and gear
change. The required pressure level is calculated
from the load condition, engine speed. Power for the
transmission system is supplied through the Trans-
mission Relay. The TCM is located in the under the
drivers seat of the vehicle.
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 (DTC). Some of these codes cause the
transmission to go into9limp-in9or9default9mode.
1
GENERAL INFORMATION

The NAG1 will default in the current gear position
if a DTC is detected, then after a key cycle or shift
to park the transmission will go into Limp-in, which
is mechanical 2nd gear. Some DTC's may allow the
transmission to resume normal operation (recover)
if the detected problem goes away. Permanent
limp-in DTC will recover when the key is cycled, but
if the same DTC is detected for three key cycles the
system will not recover and the DTC must be
cleared from the TCM with the DRBIII scan tool.
Once the DRBIIItis in the Transmission portion
of the diagnostic program, it constantly monitors
the TCM to see if the system is in limp-in mode. If
the transmission is in limp-in mode, the DRBIIIt
will flash the red LED.
3.2.1 CONTROLLER MODES OF
OPERATION
Permanent limp-in mode
When the TCM determines there is a non-
recoverable condition present that will not allow
proper transmission operation, it will place the
transmission in permanent limp-in mode. When the
condition occurs the TCM will turn off all solenoids
as well as the solenoid supply output circuit. If this
occurs while the vehicle is moving, the transmission
will remain in the current gear until the ignition is
turned off or shifter is placed in the9P9position.
Once the shifter has been placed in9P9the Trans-
mission will only allow 2nd gear operation. If the
problem occurs while the vehicle is not moving the
transmission will only allow 2nd gear operation.
Temporary limp-in mode
This mode is the same as the permanent limp-in
mode except if the condition is no longer present the
system will resume normal operation. (Recoverable
DTC)
Undervoltage limp-in mode
When the TCM detects that system voltage has
dropped below 8.5 volts it will disable voltage de-
pendant diagnostics and place the transmission in
the temporary limp-in mode. When the TCM senses
that the voltage has risen above 9.0 volts, normal
transmission operation will be resumed.
Hardware Error Mode
When the TCM detects a major internal error the
transmission will be placed in the permanent
limp-in mode and cease all communication over the
CAN bus. Once the TCM has entered this mode
normal transmission operation will not resume un-
til all DTC's are cleared from the TCM.
Loss of Drive
If the TCM detects a situation that has resulted or
may result in engine or transmission failure, the
transmission will be placed in the neutral position.Improper Ratio, Input Sensor Overspeed, or Engine
Overspeed DTC's will cause the loss of drive.
Controlled Limp-in Mode
When a failure condition does not require the TCM
to shut down the solenoid supply, but the failure is
of a degree where the TCM will place the transmis-
sion into a predefined gear, there will be several
shift performance issues. Examples of this are, with
the transmission slipping the controller will at-
tempt to place the transmission into third gear and
maintain third gear for all forward drive conditions.
Another example is some of the CAN bus message
issues if the TCM does not receive required infor-
mation from the Engine Controller, then default
values are used which may result in poor transmis-
sion shift performance.
3.2.2 MIL ILLUMINATION
For failures detected by the Transmission Con-
troller that result in the controller placing the
transmission into a limp-in mode, except for System
Overvoltage and System Undervoltage DTCs, the
MIL will be illuminated. The Transmission Control
Module will inform the ECM over the CAN bus that
a failure has occurred. The ECM will illuminate the
MIL. If the condition is removed and the failure
becomes Stored (Intermittent), the Transmission
controller will stop reporting that the DTC is active
and the ECM will extinguish the MIL.
NOTE: The MIL will light when the problem is
first detected and it will not go off until the
next ignition cycle, after all problem
conditions have been checked for their
presence. This normally takes several
minutes of driving.
3.2.3 SOLENOIDS
1-2/4-5 solenoid -The 1-2/4-5 solenoid is activated
when the TCM determines that the transmission
must shift into or out of 2nd gear or 5th gear. The
solenoid is only activated during the shifting of the
transmission. When the solenoid is activated, hy-
draulic pressure is applied to the proper shift ele-
ments in the transmission to allow the desired shift.
Once the shift is completed, the solenoid is turned
off.
2-3 solenoid -The 2-3 solenoid is activated when
the TCM determines that the transmission must
shift into or out of 3rd gear. The solenoid is only
activated during the shifting of the transmission.
When the solenoid is activated hydraulic pressure
is applied to the proper shift elements in the trans-
mission to allow the desired shift. Once the shift is
completed, the solenoid is turned off.
2
GENERAL INFORMATION

3-4 solenoid -The 3-4 solenoid is activated when
the TCM determines that the transmission must
shift into or out of 4th gear. The solenoid is only
activated during the shifting of the transmission.
When the solenoid is activated, hydraulic pressure
is applied to the proper shift elements in the trans-
mission to allow the desired shift. Once the shift is
completed, the solenoid is turned off.
TCC solenoid -The TCC solenoid is activated
when the TCM determines that the Torque con-
verter clutch should be activated. The TCC clutch is
a variable slip torque clutch that allows control of
torque converter slip from 5% to 95.5% of full TCC
engagement. The clutch is controlled by the TCC
solenoid which is pulse width modulated (PWM) to
provide the desired amount of slip.
Shift Pressure Solenoid -The Shift Pressure
Solenoid is activated when the TCM determines
that a transmission shift is required. The solenoid
is PWM controller to allow the proper amount of
hydraulic pressure to the shift elements. The sole-
noid is only activated during the shifting of the
transmission. When the solenoid is activated, hy-
draulic pressure is removed from the proper shift
elements to allow the desired shift. Once the shift is
completed, the solenoid is turned off.
Modulation pressure solenoid -The modulation
pressure is always active. The solenoid is pulse
width modulated (PWM) controlled and is used to
modulate the hydraulic system pressure to the
desired pressure.
3.2.4 TRANSMISSION COMPONENT
DESCRIPTIONS
Shift Assembly
The Shift Lever Selector transmits all selector lever
positions, as well as selected shift ranges to the
TCM over the CAN Bus. At the same time, the
selector lever positions P, R, N, and D are transmit-
ted by a cable to the selector lever shaft in the
transmission.
Brake shift inter-lock
To prevent unauthorized shifting out of the park
position, the Selector lever is locked in the Park
position until the ignition key is turned to the run
position and the brake pedal is pressed. This will
allow the driver to shift out of the park position.
Reverse Lamp Output
The Reverse Light Switch is integrated into the
shifter module and controls the reverse lights.
Reverse Inhibitor
The Shift Lever Assembly constantly monitors ABS
wheel speed to prevents an inadvertent selection of
reverse at speeds above approximately 6.4 Km/h(4MPH). The Reverse inhibitor is part of the Shift
Lever Assembly and is controlled by the Shift Lever
Assembly module.
Trans temp sensor - P/N Switch circuit
The TCM will detect the selector lever in park and
neutral positions. The TCM does this by monitoring
the Transmission temperature sensor signal along
with the shifter position signals. The P/N switch
contact is operated by a cam located in the trans-
mission which, opens a reed contact switch that is
wired in series with the transmission temperature
sensor. When the P/N contact switch is opened in
park and neutral, the TCM senses a high transmis-
sion temperature. Confirming the P/N switch sta-
tus. Note: In park or neutral, the TCM uses engine
temperature (to avoid setting a DTC). The TCM
sends a hardwired signal to the ECM that will allow
the ECM controlled start circuit to engage in P or N
only. The TCM also sends a P/N bus message to the
ECM to confirm the P/N switch status.
The Normal Transmission Temperature Sensor
resistance is between 500.0 and 2500.0 ohms.
The normal voltage limits for the transmis-
sion temperature sensor, are between 0.5 and
3.0 volts.
Input Speed Sensors
The NAG1 transmission has two input speed sen-
sors N2 and N3, both speed sensors are located on
the valve body and report DTC's for the input speed
sensors errors. The speed sensors are Hall Effect
speed sensors that are used by the TCM to calculate
the transmissions input speed. Since the input
speed could not be measured directly, two of the
drive elements are measured. Two input speed
sensors were required because both drive elements
are not active in all gears. The input sensors N2 and
N3 will report the same input speed in gears 2nd,
3rd or 4th. If the N2 and N3 input speed signals are
not the same in these gears then there is an issue
with the transmission and the DTC Input Sensors
Mismatch will be set.
The N3 input speed is not reported in1st and 5th
gears. The N2 sensor is not reported in Reverse.
The Input Speed Sensor Overspeed is a rationality
check that is intended to indicate a major transmis-
sion failure and will cause a loss of drive (place the
transmission in Neutral)
Output Speed Sensor (ABS signal)
The NAG1 transmission does not have an output
shaft speed sensor. The TCM uses the ABS (An-
tilock Brake System) Wheel Speed sensor informa-
tion, it receives over the CAN bus, to calculate the
transmissions output shaft speed. The TCM moni-
tors the ABS system for functionality and reports
ABS speed sensor and communication DTCs, which
will affect proper transmission operation.
3
GENERAL INFORMATION

3.2.5 TRANSMISSION OPERATION AND
SHIFT SCHEDULING
The transmission covered in this manual has
unique shift schedules depending on the tempera-
ture of the transmission oil. The transmission oil
temperature has a decisive effect on the shift qual-
ity of the transmission. The shift schedule is modi-
fied to extend the life of the transmission while
operating under extreme conditions and to improve
driver comfort by modifying shift schedules.
The transmission oil temperature is measured
with a Temperature Sensor on the NAG1 transmis-
sion. The Temperature Sensor is an integral com-
ponent of the Transmission Solenoid assembly. If
the Temperature Sensor is causing a problem, a
DTC will be set in the TCM.
The Transmission Temperature Sensor is wired in
series with the Park /Neutral (P/N) switch. The P/N
switch is also located in the transmission. The trans-
mission temperature is only read by the TCM when
the P/N switch closes while in the R, D position.
When the shifter lever is in the park or neutral
position, the P/N switch opens and the temperature
being displayed is Engine temperature.
AutoStick Feature (If equipped)
This feature allows the driver to manually shift the
transaxle when the shift lever is moved sideways to
the (+ / -) in position D to adjust the shift range.
3.2.6 TRANSMISSION ADAPTIVES -
INITIALIZE AND STORE
Initialize Adaptive -This TCM function should be
used when a new transmission has been placed in
the vehicle. This command will reset the TCM
adaptive to the factory setting.
Store Adaptive -This command should be used
after the vehicle has been test driven by the tech-
nician to store any learned adaptive changes that
occurred during the test drive. During normal op-
eration adaptive are updated every 10 minutes.
Using this command the latest adaptive will be
written to the TCM immediately.
3.3 DIAGNOSTIC TROUBLE CODES
Diagnostic trouble codes (DTC's) are codes stored
by the Transmission Control Module (TCM) and the
Shift Lever Assembly Module (SLA) to help diag-
nose Transmission and Shifter 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 ECM DTC's are present that could
cause a transmission complaint.
If there is a communication K-ABS,Shifter or
K-TCM circuit problem, trouble codes will not be
accessible until the problem is fixed. The DRBIIIt
will display an appropriate message. The following
is a possible list of causes for a bus problem:
± open or short to ground/battery in K line
circuit.
± internal failure of any module or component
connected to the K line circuit
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.
If the TCM records a DTC that will adversely
affect the vehicles transmission, it will request (via
the communication bus) that the ECM illuminate
the Malfunction Indicator Lamp (MIL). All trans-
mission DTC's will be stored in the TCM.
3.3.1 ACTIVE (HARD) CODE
Any Diagnostic Trouble Code (DTC) that is set
whenever the system or component is monitored is
an Active code. This means that the problem is
there every time the TCM checks that system or
component. Some codes will set immediately at
start up and others will require a road test under
specific conditions to set the DTC. It must be
determined if a code is Active (repeatable) or Stored
(Intermittent) before attempting diagnosis.
3.3.2 STORED (INTERMITTENT) CODE
A diagnostic trouble code that is not there every
time the TCM checks the circuit or function is a
Stored (Intermittent) code. 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. If the DTC is reset (after an
ignition cycle) the DTC will be set to Stored (Inter-
mittent) status. A DTC status can be9Active9or
9Stored9(Intermittent). Active is when the DTC is
present in the controller and the transmission is in
the particular mode of operation for that DTC.
Stored means that the DTC occurred at some point,
but is not currently present, or the conditions have
not been right to check for the presence of the
problem, when a DTC is classified as Stored (Inter-
mittent), no TCM reaction is required.
4
GENERAL INFORMATION

Emergency running function
If DTCs occur, safe-driving conditions must be re-
tained but full functionality of the transmission will
be limited to avoid damaging the automatic trans-
mission. In the event of certain DTCs the TCM
switches to emergency running. The TCM will store
the appropriate DTC codes and solenoids will be
de-energized (turned off)
The transmission effects will be:
²The last gear shifted remains in that position
²The modulating pressure and shift pressure in-
crease to maximum value
²The torque converter clutch is disengaged
(turned off)
Shifting manually after a DTC detection
NOTE: The vehicle can still be shifted
manually to 2nd or reverse gear.
To accomplish these shifts you must
Stop the vehicle
Turn the ignition off
Start the engine
Place the selector lever into D for 2nd gear
Place the selector lever into R for reverse gear
The emergency running function is retained until
the DTC is eliminated or the stored DTC code is
erased.
Stored (Intermittent) DTCs can be reset by cy-
cling the ignition switch
3.3.3 TROUBLE CODE ERASURE
Diagnostic Trouble Codes can be erased in two
ways. The first is to erase the DTC with the DRBIII
or scan tool. The second is if the DTC is no longer
present, the DTC is reset by the TCM (after an
ignition cycle), which will place the DTC in an
intermittent status (Stored DTC).
When there are no diagnostic trouble codes
stored in memory, the DRBIIItwill display
(NO DTC's DETECTED(
3.4 USING THE DRBIIIT
Refer to the DRBIIItuser's guide for instructions
and assistance with reading trouble codes, erasing
trouble codes, and other DRBIIItfunctions.
3.5 DRBIIITERROR MESSAGES
Under normal operation, the DRBIIItwill display
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.
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 DRBI-
IItand 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.
4.0 DISCLAIMERS, SAFETY,
AND WARNINGS
4.1 DISCLAIMERS
All information, illustrations, and specifications
contained in this manual are based on the latest
5
GENERAL INFORMATION