Page 116 from 126
Appendix ATroubleshooting and
If the display does not light up when you connect the Scanner to vehicle power, check:
•The Scanner battery, located under the left handgrip.
•For a blown cigarette lighter fuse on the vehicle if using the cigarette lighter power cable.
•For bent or broken pins on both ends of the data cable and on the test adapter.
•For a loose cable connection.
•For an open ground wire in the vehicle connector wiring harness.
•For correct connection at the battery if you are using the battery power adapter.
Replace the internal battery if the Scanner operates erratically in any way or if recorded data is
not retained in the Scanner memory.
If the display is very dim or nearly blank when you apply power to the Scanner, remove the
internal battery with the Scanner disconnected from vehicle power. Hold down the Quick ID
Button for 5 seconds to clear the Scanner memory. Then reinstall the battery.
If one or more segments of the display do not light during the display check, you may not get
valid readings when viewing data or doing functional tests.
See “Communication Problems” on page 110 for information on what to do if a vehicle does not
communicate with the Scanner.
To test Mercedes control systems, the Scanner must communicate with the engine or
transmission controller and receive vehicle data over a data link.
The speed at which the Scanner operates and displays data depends on the number of data
parameters and how busy the control system is on the vehicle.
This can affect how quickly the data changes on the Scanner display and the length of time it
takes to display a movie. Differences in Scanner operation will vary from vehicle to vehicle. On
one car, data readings may appear to change almost instantly, while on another vehicle, data
changes may occur much slower.
The Data and Codes selections from the Main Menu require the Scanner to communicate with
the vehicle control module. The ignition must be on to establish communication. After selecting
Data or Codes, the Scanner displays an initializing message.
If communication is not established within 5 seconds, the Scanner displays a “no
communication” message. Return to the System List Menu and check the items listed below
under Common Problems.
Page 117 from 126
111 Troubleshooting and Communication Problems Common Problems
Some common problems that may prevent communication between the Scanner and ECU are
1. Vehicle identification—Check the vehicle identification entered from the VIN plate. If in doubt,
reenter the identification.
2. Scanner connections—See “Check Scanner Connection and Operation” on page 111 for
information on Scanner cables and connections.
3. Ignition off when connecting Scanner—Be sure the ignition is off when connecting and
disconnecting the Scanner. If the ignition is on when the Scanner is connected or
disconnected, Scanner memory may be disrupted. Erase and reenter the vehicle
identification if this occurs.
4. Loss of power to the computer—The computer receives battery voltage through one or more
fusible links in the wiring harness. Use a wiring diagram to check computer connections for
battery voltage and ground. If a fusible link is open, the computer cannot communicate with
5. Loss of power to the Scanner when using the optional Power Pac kit accessory—The Power
Pac provides external battery power to the Scanner, independently of the vehicle. The Power
Pac requires periodic charging using the adapter included in the kit. A discharged Power Pac
can cause the Scanner display to flicker or extinguish without warning, terminating
If the Scanner displays the no communication message, it means that the Scanner and the
vehicle computer simply cannot communicate with each other for some reason. If the no
communication message appears, check the vehicle battery state of charge, and check the
Scanner data cable continuity as described below.
Check Scanner Connection and Operation
If the Scanner fails to light up or if the readings are unsteady, the Scanner may be at fault. If the
Scanner intermittently resets or goes blank, a wire may be opening intermittently in one of the
cables or in the adapter.
Check the following points:
•Use an ohmmeter to test the continuity of the Scanner power cable.
•Use an ohmmeter to test the continuity of the Scanner data cable. Measure continuity pin to
pin from the connectors at each end of the cable.
Page 118 from 126
Appendix BTerms, Abbreviations and
Te r m s
The following terms are used throughout this manual to explain certain operations and displays:
Abbreviations and Acronyms
The following terms abbreviations and acronyms are used in diagnostic trouble code definitions
displayed by the Scanner, or used in Mercedes literature.
blink codeA type of vehicle control system that has no serial data. Any trouble codes the
control system set are extracted either by flashing the malfunction indicator lamp
(MIL) or using special digitized break-out box.
codeA numerical code, generated by the vehicle control system to indicate a fault has
occurred in a particular subsystem, circuit, or part.
cursorThe arrow that appears on menus and some other displays. In most displays, the
cursor moves as you scroll.
fixTo lock a single line of the display in a fixed position on the screen to prevent it from
scrolling. Data readings remain live while the parameter categories are fixed.
frameOne complete data package, or transmission cycle, from a vehicle that provides
serial data of control system operating parameters.
holdTo capture and hold a single data frame for review or printing. Data readings
(measured values) are locked at the frame that is held, while parameter and code
lines can be scrolled. A data frame may be held while selected lines are either fixed
movieA vehicle data record whose length depends on the number of selected data
menuA list of vehicle tests or programs from which a selection can be made. Scroll to
place the cursor at the desired function on a menu and press Y to enter the function.
4MATIC automatically controlled four-wheel drive
AAC automatic air conditioning
AAM all activity module
ABC active body control
ABL exterior lights
ABS antilock brake system
ABW distance warner
A/C air conditioning (automatic or Tempmatic)
ACRS automatic child seat recognition
ADM automatic dimming mirror, inside rear view
ADS automatic damping system, electronic suspension
Page 119 from 126
11 3 Terms, Abbreviations and Acronyms Abbreviations and Acronyms
AFE automatic lane recognition
AG automatic transmission
AGW audio gateway
AHV trailer hitch
AIR secondary air injection
AKR anti-knock control
AKSE automatic child seat recognition
ALDA barometric pressure/charge air pressure compensation
AP accelerator pedal
APS auto pilot system
ARF exhaust gas recirculation
ARMIN airbag with integrated emergency call system
AS antenna system
ASA automatic dimming mirror
ASD automatic slip differential, limited-slip
ASF IFI diesel system
ASG Sequentronic automated manual transmission
ASR acceleration slip regulation, traction control
AT automatic transmission
ATA anti-theft alarm
ATS antenna systems
AWR distance warning radar
BA backup assist
BARO barometric pressure
BAS brake assist
BCAPC barometric charge air pressure compensation
BDC bottom dead center
BMbase module, also called general module (GM) or controller area network (can) bus
BPC barometric pressure compensation
CA cooling/closing assist
CAN controller area network
CC cruise control
CCM combination control module
CDC compact disc changer
CDI common rail diesel injection
CDW CD changer
CF convenience feature
CFI continuous fuel injection
CKA crankshaft angle
CKP crankshaft position
CL central locking
CLUS instrument cluster
CMP camshaft position
Page 120 from 126
11 4 Terms, Abbreviations and Acronyms Abbreviations and Acronyms
CNS communication and navigation system
COMAND cockpit management and data system
CST cabriolet/convertible soft top
CTEL cellular telephone
CTP closed throttle position
CTU central triggering unit
CV convertible soft top
D2B D2 bus
DAS drive authorization system
DBE overhead control panel control module
DCM door controller
DH diagnosis manual
DI distributor ignition
DI1 DI for right bank of 12-cylinder
DI2 DI for left bank of 12-cylinder
DM diagnostic module
DMAN diagnosis manual
DSV drive authorization shut-off valve
DTC diagnostic trouble code
DTR Distronic (autonomous intelligent cruise control)
EA electronic accelerator
EAG electronic transmission 722.5
EAM extended activity module
EATC electronic automatic transmission control
EBR electronic braking regulation
E-call emergency call system
ECI electronic controlled ignition
ECL engine coolant level
ECT engine coolant temperature
EDC electronic diesel control
EDR electronic diesel regulation
EDS electronic diesel system
EDW anti-theft alarm system
EFH power windows
EFP electronic accelerator
EGR exhaust gas recirculation
EGS electronic transmission 722.6
EHD electronic high-pressure diesel injection system
EI electronic ignition, distributorless
EIFI electronic inline fuel injection
EIS electronic ignition and starter switch
EL exterior lighting
ELR electronic idle speed control
ELV electric steering lock