
MAINTENANCE - WITH ASSYST MAINTENANCE
COMPUTER
ASSYST provides information on the best possible
timing for maintenance work.
NOTE: The engine manufacturer strongly recom-
mends the use of synthetic engine oils, such as
TMobil 1 SAE 0W-40.
When the next maintenance service is due, this
will be indicated in the multi-function display with
the wrench icon symbol displayed in km/miles or
days.
²One wrench icon showing indicates Oil Service
is necessary.
²Two wrench icons showing indicates Mainte-
nance Service is necessary ± displayed in km/miles or
days.
If the display shows the number of days, a clock
symbol will also appear in the multi-function display.
You should have the maintenance performed
within the stated period/distance.
The service indicator should be reset after an oil
service and/or maintenance service has been per-
formed.
REGULAR CHECK-UPS
To maintain the safe operation of the vehicle, it is
recommended that the following tasks be performed
on a regular basis (i.e. weekly or whenever the vehi-
cle is refueled). Check:
²Engine oil level
²Brake system, clutch mechanism ± fluid level
²Battery ± acid level
²Windshield washer system and headlamp clean-
ing system ± fluid level
²Mechanical assemblies (e. g. engine, transmis-
sion, etc.) ± check for leaks
²Condition of tires and tires pressures
²All exterior lights
SPECIAL MAINTENANCE REQUIREMENTS
If bodies built by manufacturers other than
DaimlerChrysler Corporation are fitted to the vehi-
cle, the maintenance requirements and lubrication
intervals specified by the body manufacturer must be
adhered to, in addition to all standard maintenance
requirements.
Brake Fluid
Only use brake fluids approved by the manufac-
turer (DOT 4 plus).
Coolant
Corrosion inhibitor/antifreeze concentration in the
coolant should be checked before the onset of winter
(once year in countries with high prevailing temper-
atures).Replace the coolant every five years or 100,000
miles.
Dust Filter for Heating/Ventilation Replace-
ment
The dust filter and the tailgate interior filter are to
be renewed during routine maintenance service. If
operating conditions are dusty, these filters should be
renewed more frequently.
ENGINE OIL CHANGE AND FILTER REPLACEMENT
At the minimum, change the engine oil and oil fil-
ter once a year ± even if the vehicle mileage per year
is extremely low. For standard oil service schedules
refer to the chapter oil service and maintenance ser-
vice.
Once a Year
Select the viscosity of the engine oil (SAE classes)
according to the outside air temperature.
Only use engine oil approved by DaimlerChrysler
Corporation if following the ASSYST system guide-
lines.
If the fuel used has a sulphur content exceeding
0.05% by weight, the service intervals should be split
in half.
SCOPE OF WORK FOR MAINTENANCE SERVICE
Oil Service
²Engine:
Oil change and filter replacement
Check fluid levels of the following system,
refill as necessary.
²If fluid is lost, trace and eliminate cause ± as a
separate order.
²Power-assisted steering
Lubrication work:
²Trailer tow hitch (original equipment)
Maintenance
²ASSYST maintenance computer reset
Function check
²Signalling system, warning and indicator lamps
²Headlamps, exterior lighting
²Windshield wipers, windshield washer system
Check for leaks and damage.
²Check for abrasion points and ensure that lines
are correctly routed!
²All lines and hoses, sensor cables
²Rubber boots on front axle drive shafts, rubber
boots on front axle suspension ball joints, shock
absorbers
Check fluid levels for the following systems,
correct as necessary.
NOTE: Should there be a loss of fluid which cannot
be explained by regular use, trace and eliminate the
cause.
0 - 8 LUBRICATION & MAINTENANCEVA
MAINTENANCE SCHEDULES (Continued)

The TCM continuously checks for electrical prob-
lems, mechanical problems, and some hydraulic prob-
lems. When a problem is sensed, the TCM stores a
diagnostic trouble code (DTC). Some of these codes
cause the transmission to go into9Limp-In9or
9default9mode. Some DTCs cause permanent
Limp-In and others cause temporary Limp-In. The
NAG1 defaults in the current gear position if a DTC
is detected, then after a key cycle the transmission
will go into Limp-in, which is mechanical 2nd gear.
Some DTCs may allow the transmission to resume
normal operation (recover) if the detected problem
goes away. A 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 DRBIIItscan tool.
TCM SIGNALS
The TCM registers one part of the input signals by
direct inputs, the other part by CAN C bus. In addi-
tion to the direct control of the actuators, the TCM
sends various output signals by CAN C bus to other
control modules.
Selector Lever Position
The TCM monitors the SLA for all shift lever posi-
tions via the CAN bus.
ATF Temperature Sensor
The ATF temperature sensor is a positive temper-
ature co-efficient (PTC) thermistor. It measures the
temperature of the transmission fluid and is a direct
input signal for the TCM. The temperature of the
ATF has an influence on the shifttime and resulting
shift quality. As the temperature rises, resistance
rises, and therefore, the probing voltage is decreas-
ing. Because of its registration, the shifting process
can be optimized in all temperature ranges.
The ATF temperature sensor is wired in series
with the park/neutral contact. The temperature sig-
nal is transmitted to the TCM only when the reed
contact of the park/neutral contact is closed because
the TCM only reads ATF temperature while in any
forward gear, or REVERSE. When the transmission
is in PARK or NEUTRAL, the TCM will substitute
the engine temperature for the ATF temperature.
Starter Interlock
The TCM monitors a contact switch wired in series
with the transmission temperature sensor to deter-
mine PARK and NEUTRAL positions. The contact
switch is open in PARK and NEUTRAL. The TCM
senses transmission temperature as high (switch
supply voltage), confirming switch status as open.
The TCM then broadcasts a message over CAN bus
to confirm switch status. The PCM receives thisinformation and allows operation of the starter cir-
cuit.
N2 and N3 Speed Sensors
The N2 and N3 Input Speed Sensors are two Hall-
effect speed sensors that are mounted internally in
the transmission and are used by the TCM to calcu-
late the transmission's input speed. Since the input
speed cannot 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.
CAN C Bus Indirect Input Signals
A 2.5-volt bias (operating voltage) is present on the
CAN C bus any time the ignition switch is in the
RUN position. Both the TCM and the ABS apply this
bias. On this vehicle, the CAN C bus is used for mod-
ule data exchange only. The indirect inputs used on
the NAG1 electronic control system are:
²Wheel Speed Sensors.
²Brake Switch.
²Engine RPM.
²Engine Temperature.
²Cruise Control Status.
²Gear Limit Request.
²Throttle Position - 0% at idle, 100% at WOT. If
open, TCM assumes idle (0% throttle opening).
²Odometer Mileage
²Maximum Effective Torque.
²Engine in Limp-In Mode/Mileage Where DTC
Was Set.
BRAKE TRANSMISSION SHIFT INTERLOCK (BTSI)
The BTSI solenoid prevents shifting out of the
PARK position until the ignition key is in the RUN
position and the brake pedal is pressed. The TCM
controls the ground while the ignition switch supplies
power to the BTSI solenoid. The PCM monitors the
brake switch and broadcasts brake switch status
messages over the CAN C bus. If the park brake is
depressed and there is power (Run/Start) to SLA, the
BTSI solenoid deactivates.
SHIFT SCHEDULES
The basic shift schedule includes up and down-
shifts for all five gears. The TCM adapts the shift
program according to driving style, accelerator pedal
position and deviation of vehicle speed. Influencing
factors are:
²Road Conditions.
²Incline, Decline and Altitude.
²Trailer Operation, Loading.
²Engine Coolant Temperature.
²Cruise Control Operation.
²Sporty Driving Style.
8E - 6 ELECTRONIC CONTROL MODULESVA
TRANSMISSION CONTROL MODULE (Continued)

arate take out and connector of the vehicle wire
harness.
Located between the rear cover and the cluster
hood is the cluster housing. The molded plastic clus-
ter housing serves as the carrier for the cluster elec-
tronic circuit board and circuitry, the cluster
connector receptacles, the gauges, a Light Emitting
Diode (LED) for each cluster indicator and general
illumination lamp, the multi-function indicator LCD
unit, electronic tone generators, the cluster overlay,
the gauge pointers, the multi-function indicator
switches and the four switch push buttons.
The cluster overlay is a laminated plastic unit. The
dark, visible, outer surface of the overlay is marked
with all of the gauge dial faces and graduations, but
this layer is also translucent. The darkness of this
outer layer prevents the cluster from appearing clut-
tered or busy by concealing the cluster indicators
that are not illuminated, while the translucence of
this layer allows those indicators and icons that are
illuminated to be readily visible. The underlying
layer of the overlay is opaque and allows light from
the LED for each of the various indicators and illu-
mination lamps behind it to be visible through the
outer layer of the overlay only through predeter-
mined cutouts. A rectangular opening in the overlay
at the base of the speedometer provides a window
through which the illuminated multi-function indica-
tor LCD unit can be viewed.
Several versions of the EMIC module are offered
on this model. These versions accommodate all of the
variations of optional equipment and regulatory
requirements for the various markets in which the
vehicle will be offered. The microprocessor-based
EMIC utilizes integrated circuitry, Electrically Eras-
able Programmable Read Only Memory (EEPROM)
type memory storage, information carried on the
Controller Area Network (CAN) data bus, along with
several hard wired analog and multiplexed inputs to
monitor systems, sensors and switches throughout
the vehicle.
In response to those inputs, the hardware and soft-
ware of the EMIC allow it to control and integrate
many electronic functions and features of the vehicle
through both hard wired outputs and the transmis-
sion of electronic message outputs to other electronic
modules in the vehicle over the CAN data bus. (Refer
to 8 - ELECTRICAL/ELECTRONIC CONTROL
MODULES/COMMUNICATION - DESCRIPTION -
CAN BUS).
Besides typical instrument cluster gauge and indi-
cator support, the electronic functions and features
that the EMIC supports or controls include the fol-
lowing:
²Active Service System- In vehicles equipped
with the Active Service SYSTem (ASSYST) engine oilmaintenance indicator option, the EMIC electronic
circuit board includes a second dedicated micropro-
cessor. This second microprocessor evaluates various
data including time, mileage, and driving conditions
to calculate the required engine oil service intervals,
and provides both visual and audible alerts to the
vehicle operator when certain engine oil maintenance
services are required.
²Audible Warnings- The EMIC electronic cir-
cuit board is equipped with an audible tone generator
and programming that allows it to provide various
audible alerts to the vehicle operator, including buzz-
ing and chime tones. An audible contactless elec-
tronic relay is also soldered onto the circuit board to
produce audible clicks that is synchronized with turn
signal indicator flashing to emulate the sounds of a
conventional turn signal or hazard warning flasher.
These audible clicks can occur at one of two rates to
emulate both normal and bulb-out turn or hazard
flasher operation. (Refer to 8 - ELECTRICAL/
CHIME/BUZZER - DESCRIPTION).
²Panel Lamps Dimming Control- The EMIC
provides a hard wired 12-volt Pulse-Width Modulated
(PWM) output that synchronizes the dimming level
of all panel lamps dimmer controlled lamps with that
of the cluster general illumination lamps and multi-
function indicator.
The EMIC houses four analog gauges and has pro-
visions for up to nineteen indicators (Fig. 3). The
EMIC includes the following analog gauges:
²Coolant Temperature Gauge
²Fuel Gauge
²Speedometer
²Tachometer
The EMIC includes provisions for the following
indicators (Fig. 3):
²Airbag (SRS) Indicator
²Antilock Brake System (ABS) Indicator
²Brake Indicator
²Brake Wear Indicator
²Charging Indicator
²Clogged Fuel Filter Indicator
²Coolant Low Indicator
²High Beam Indicator
²Low Fuel Indicator
²Malfunction Indicator Lamp (MIL)
²Multi-Function Indicator (LCD)
²Seatbelt Indicator
²Traction Control (ASR) Indicator
²Traction Control (ASR) Malfunction Indica-
tor
²Turn Signal (Right and Left) Indicators
²Washer Fluid Indicator
²Wait-To-Start Indicator
²Water-In-Fuel Indicator
VAINSTRUMENT CLUSTER 8J - 3
INSTRUMENT CLUSTER (Continued)

TIRES
DESCRIPTION
DESCRIPTION - TIRES
Tires are designed and engineered for each specific
vehicle. They provide the best overall performance
for normal operation. The ride and handling charac-
teristics match the vehicle's requirements. With
proper care they will give excellent reliability, trac-
tion, skid resistance, and tread life.
Driving habits have more effect on tire life than
any other factor. Careful drivers will obtain in most
cases, much greater mileage than severe use or care-
less drivers. A few of the driving habits which will
shorten the life of any tire are:
²Rapid acceleration
²Severe brake applications
²High speed driving
²Excessive speeds on turns
²Striking curbs and other obstacles
Radial-ply tires are more prone to irregular tread
wear. It is important to follow the tire rotation inter-
val shown in the section on Tire Rotation, (Refer to
22 - TIRES/WHEELS - STANDARD PROCEDURE).
This will help to achieve a greater tread life.
TIRE IDENTIFICATION
Tire type, size, aspect ratio and speed rating are
encoded in the letters and numbers imprinted on the
side wall of the tire. Refer to the chart to decipher
the tire identification code (Fig. 11).
Performance tires have a speed rating letter after
the aspect ratio number. The speed rating is not
always printed on the tire sidewall. These ratings
are:
²Qup to 100 mph
²Rup to 106 mph
²Sup to 112 mph
²Tup to 118 mph
²Uup to 124 mph
²Hup to 130 mph
²Vup to 149 mph
²Zmore than 149 mph (consult the tire manu-
facturer for the specific speed rating)
An All Season type tire will have eitherM+S,M
&SorM±S(indicating mud and snow traction)
imprinted on the side wall.
TIRE CHAINS
Tire snow chains may be used oncertainmodels.
Refer to the Owner's Manual for more information.
DESCRIPTION - RADIAL ± PLY TIRES
Radial-ply tires improve handling, tread life and
ride quality, and decrease rolling resistance.
Radial-ply tires must always be used in sets of
four. Under no circumstances should they be used on
the front only. They may be mixed with temporary
spare tires when necessary. A maximum speed of 50
MPH is recommended while a temporary spare is in
use.
Radial-ply tires have the same load-carrying capac-
ity as other types of tires of the same size. They also
use the same recommended inflation pressures.
The use of oversized tires, either in the front or
rear of the vehicle, can cause vehicle drive train fail-
ure. This could also cause inaccurate wheel speed
signals when the vehicle is equipped with Anti-Lock
Brakes.
The use of tires from different manufactures on the
same vehicle is NOT recommended. The proper tire
pressure should be maintained on all four tires.
DESCRIPTION - TIRE PRESSURE FOR HIGH
SPEEDS
Where speed limits allow the vehicle to be driven
at high speeds, correct tire inflation pressure is very
important. For speeds up to and including 120 km/h
(75 mph), tires must be inflated to the pressures
Fig. 11 Tire Identification
22 - 6 TIRES/WHEELSVA

WHEELS
DESCRIPTION
Original equipment wheels are designed for the
specified Maximum Vehicle Capacity.
All models use steel or aluminum wheels.
Aluminum wheels require special balance weights
and alignment equipment.
(1) On vehicles equipped with dual rear wheels,
The slots in the wheel must be aligned to provide
access to the valve stem.
OPERATION
The wheel (Fig. 19) has raised sections between
the rim flanges and the rim well. Initial inflation of
the tire forces the bead over these raised sections. In
case of tire failure, the raised sections hold the tire
in position on the wheel until the vehicle can be
brought to a safe stop.
DIAGNOSIS AND TESTING
WHEEL INSPECTION
Inspect wheels for:
²Excessive run out
²Dents or cracks
²Damaged wheel lug nut holes
²Air Leaks from any area or surface of the rim
NOTE: Do not attempt to repair a wheel by hammer-
ing, heating or welding.
If a wheel is damaged an original equipment
replacement wheel should be used. When obtainingreplacement wheels, they should be equivalent in
load carrying capacity. The diameter, width, offset,
pilot hole and bolt circle of the wheel should be the
same as the original wheel.
WARNING: FAILURE TO USE EQUIVALENT REPLACE-
MENT WHEELS MAY ADVERSELY AFFECT THE
SAFETY AND HANDLING OF THE VEHICLE. USED
WHEELS ARE NOT RECOMMENDED. THE SERVICE
HISTORY OF THE WHEEL MAY HAVE INCLUDED
SEVERE TREATMENT OR VERY HIGH MILEAGE. THE
RIM COULD FAIL WITHOUT WARNING.
STANDARD PROCEDURE
STANDARD PROCEDURE - WHEEL
REPLACEMENT
The wheel stud/lugs are designed for specific appli-
cations. They must be replaced with equivalent parts.
Do not use replacement parts of lesser quality or a
substitute design.
Before installing the wheel, be sure to remove any
build up of corrosion on the wheel mounting surfaces.
Ensure wheels are installed with good metal-to-metal
contact. Improper installation could cause loosening
of wheel nuts. This could affect the safety and han-
dling of your vehicle.
To install the wheel, first position it properly on
the mounting surface. All wheel nuts should then be
tightened just snug. Gradually tighten them in
sequence to the proper torque specification.Never
use oil or grease on studs.
Wheels must be replaced if they have:
²Excessive runout
²Bent or dented
²Leak air through welds
²Have damaged bolt holes
Wheel repairs employing hammering, heating, or
welding are not allowed.
Original equipment wheels are available through
your dealer. Replacement wheels from any other
source should be equivalent in:
²Load carrying capacity
²Diameter
²Width
²Offset
²Mounting configuration
Failure to use equivalent replacement wheels may
affect the safety and handling of your vehicle.
Replacement withusedwheels is not recommended.
Their service history may have included severe treat-
ment.
Fig. 19 Safety Rim
1 - FLANGE
2 - RIDGE
3 - WELL
VATIRES/WHEELS 22 - 11

CABIN HEATER
TABLE OF CONTENTS
page page
CABIN HEATER
DESCRIPTION.........................72
OPERATION...........................72
DIAGNOSIS AND TESTING - DIESEL
SUPPLEMENTAL HEATER - DCHA........72
EXHAUST TUBE
REMOVAL.............................73
INSTALLATION.........................73
FUEL DOSING PUMP
DESCRIPTION.........................74
OPERATION...........................74
REMOVAL.............................74
INSTALLATION.........................74
FUEL LINE
STANDARD PROCEDURE - CLEANING......75REMOVAL.............................75
INSTALLATION.........................76
HEATER UNIT
REMOVAL
REMOVAL...........................77
REMOVAL...........................77
INSTALLATION
INSTALLATION.......................78
INSTALLATION.......................78
INLET HOSE
REMOVAL.............................78
INSTALLATION.........................78
CABIN HEATER
DESCRIPTION
Vehicles equipped with the optional diesel engine
are also equipped with a supplemental heater unit.
This unit is mounted under the vehicle and operates
similar to an oil fired furnace. The heater burns
small amounts of fuel to provide additional heat to
the coolant. Coolant is routed from the engine, to the
supplemental heater, and then to the front heater
core. This provides additional heat to the passenger
compartment. The system is interfaced to the vehi-
cles on-board computer systems and DRBIIItdiag-
nostics.
The supplemental heater unit has an electronic
control module that monitors the heat output of the
heater. The heater operates at full load (5 kW), half
load or idle mode (no additional heat) depending on
coolant temperature.
OPERATION
The supplemental heater is activated via the tem-
perature control on the heater-A/C control. The
heater is activated when the temperature control is
set to/or above the upper set point. The supplemental
heater can operate in a full or partial load range aswell as an idle mode, all dependent on the engine
coolant temperature. The heater unit will also turn
off if the temperature control is set to less than the
lower set point. The supplemental heater can take up
to three minutes to completely shut down when
either the heater temperature is set below the lower
set point or the vehicle ignition is turned off.
The supplemental heater only operates when the
engine is running, the mileage exceeds 8 kilometer (5
mph) and the fuel tank volume exceeds 1/8 of a tank.
The heater should start if the coolant temperature is
below 40É C (104É F).
NOTE: Do not apply a strong vacuum directly on
the supplemental heater exhaust line. Place the vac-
uum within 75 mm (3 inches) of the exhaust port.
Too strong of a vacuum can prevent the heater from
starting. The heater control module monitors the
supplemental blower speed and combustion during
its start-up.DIAGNOSIS AND TESTING - DIESEL
SUPPLEMENTAL HEATER - DCHA
Refer to the Symptoms Diagnosis table for basic
checks of the diesel fueled supplemental heater.
24 - 72 CABIN HEATERVA