WABCO OnGuard User manual

ONGUARD™COLLISION
SAFETY SYSTEM
MAINTENANCE MANUAL

Service Notes
Information contained in this publication was in effect at the time the publication
was approved for printing and is subject to change without notice or liability.
WABCO reserves the right to revise the information presented or to discontinue the
production of parts described at any time.
WABCO Maintenance Manual MM-0951 (Revised 08-18)
About This Manual
This service manual applies to all vehicles equipped with the
OnGuard™ Collision Safety System.
Before You Begin
1. Read and understand all instructions and procedures before
you begin to service components.
2. Read and observe all Warning and Caution hazard alert
messages in this publication. They provide information that can
help prevent serious personal injury, damage to components,
or both.
3. Follow your company’s maintenance and service, installation
and diagnostics guidelines.
4. Use special tools when required to help avoid serious personal
injury and damage to components.
Hazard Alert Messages and Torque
Symbols
WARNING
A Warning alerts you to an instruction or procedure that you
must follow exactly to avoid serious personal injury and
damage to components.
CAUTION
A Caution alerts you to an instruction or procedure that you
must follow exactly to avoid damage to components.
@This symbol alerts you to tighten fasteners to a specified torque
value.
How to Obtain Additional Maintenance
and Service Information
Visit Literature on Demand at WABCO-auto.com to access and order
product, service, aftermarket, and warranty literature for WABCO’s
truck, trailer and specialty vehicle components.
How to Obtain Tools and Supplies
Specified in This Manual
Call WABCO’s Commercial Vehicle Aftermarket at 888-725-9355 to
obtain WABCO tools and supplies.

Contents
pg. iAsbestos and Non-Asbestos Fibers
1Section 1: Introduction
Overview
How OnGuard Works
2 System Components
4Section 2: Diagnostics, Troubleshooting and
Testing
General Information
Radar Sensor and Display Software Levels
Fault Codes
5 Troubleshooting Guide
6 TOOLBOX Software Diagnostics
12 Radar Software Version USO 1.XXXX Fault Code Table
22 Radar Software Version USO 2.XXXX Fault Code Table
47 Radar Inspection and Preventive Maintenance
Radar System Troubleshooting
51 Electrical System and Harnesses Troubleshooting
53 Component Message Fault Troubleshooting
54 Cruise Control System Troubleshooting
55 Anti-lock Braking System (ABS) Troubleshooting
57 Section 3: Component Replacement
Radar Sensor
59 Display Replacement
60 Section 4: Appendix
Product Information Letter #504

Asbestos and Non-Asbestos Fibers
i
WABCO Maintenance Manual MM-0951 (Revised 08-18)
ASBESTOS FIBERS WARNING
The followingproceduresfor servicingbrakesare recommendedto reduce exposure to
asbestosfiber dust, a cancer andlungdisease hazard. Material Safety Data Sheetsare
available from WABCO.
Hazard Summary
Becausesomebrakelinings contain asbestos, workers who servicebrakes must understandthe
potential hazards of asbestos andprecautions for reducing risks. Exposureto airborneasbestos
dust can causeserious andpossibly fatal diseases, including asbestosis (achronic lung disease)
andcancer, principally lung cancer andmesothelioma(acancer of thelining of thechest or
abdominal cavities). Somestudies show that therisk of lung cancer among persons who smoke
andwho areexposed to asbestos is much greater than therisk for non-smokers. Symptoms of
thesediseases may not becomeapparent for 15, 20 or moreyears after thefirst exposureto
asbestos.
Accordingly, workers must usecaution to avoidcreating andbreathing dust when servicing brakes.
Specific recommended work practices for reducing exposureto asbestos dust follow. Consult your
employer for moredetails.
Recommended Work Practices
1. SeparateWork Areas. Whenever feasible, servicebrakes in aseparatearea away from other
operations to reducerisks to unprotected persons. OSHA has set amaximum allowablelevel of
exposurefor asbestos of 0.1 f/cc as an 8-hour time-weighted averageand1.0 f/cc averaged over
a30-minuteperiod. Scientists disagree,however, to what extent adherenceto themaximum
allowableexposurelevels will eliminatetherisk of diseasethat can result from inhaling asbestos
dust. OSHA requires that thefollowing sign be posted at theentranceto areas whereexposures
exceed either of themaximum allowablelevels:
DANGER: ASBESTOS
CANCER AND LUNGDISEASE HAZARD
AUTHORIZED PERSONNEL ONLY
RESPIRATORSAND PROTECTIVE CLOTHING
ARE REQUIRED IN THISAREA.
2. Respiratory Protection. Wear arespirator equipped with ahigh-efficiency (HEPA) filter
approved by NIOSH or MSHA for usewith asbestos at all times when servicing brakes, beginning
with theremoval of thewheels.
3. Procedures for Servicing Brakes.
a. Enclosethebrakeassembly within anegativepressureenclosure. Theenclosureshouldbe
equipped with aHEPA vacuum andworker arm sleeves. With theenclosurein place, usethe
HEPA vacuum to loosen andvacuum residuefrom thebrakeparts.
b. As an alternativeprocedure, useacatch basin with water andabiodegradable,
non-phosphate, water-based detergent to wash thebrakedrum or rotor andother brake
parts. Thesolution shouldbe applied with low pressureto prevent dust from becoming
airborne. Allow thesolution to flow between thebrakedrum andthebrakesupport or the
brakerotor andcaliper. Thewheel hubandbrakeassembly components shouldbe thoroughly
wetted to suppress dust beforethebrakeshoes or brakepads areremoved.Wipethebrake
parts clean with acloth.
c. If an enclosed vacuum system or brakewashing equipment is not available, employers may
adopt their own written procedures for servicing brakes, provided that theexposurelevels
associated with theemployer’s procedures do not exceed thelevels associated with the
enclosed vacuum system or brakewashing equipment. Consult OSHA regulations for more
details.
d. Wear arespirator equipped with aHEPA filter approved by NIOSH or MSHA for usewith
asbestos when grinding or machining brakelinings. In addition, do such work in an area with
alocal exhaust ventilation system equipped with aHEPA filter.
e. NEVER usecompressed air by itself, dry brushing, or avacuum not equipped with aHEPA
filter when cleaning brakeparts or assemblies. NEVER usecarcinogenic solvents, flammable
solvents, or solvents that can damagebrakecomponents as wetting agents.
4. Cleaning Work Areas. Clean work areas with avacuum equipped with aHEPA filter or by wet
wiping. NEVER usecompressed air or dry sweeping to clean work areas. When you empty vacuum
cleaners andhandleused rags, wear arespirator equipped with aHEPA filter approved by NIOSH
or MSHA for usewith asbestos. When you replaceaHEPA filter, wet thefilter with afinemist of
water anddisposeof theused filter with care.
5. Worker Clean-Up. After servicing brakes, wash your hands beforeyou eat, drink or smoke.
Shower after work. Do not wear work clothes home. Useavacuum equipped with aHEPA filter to
vacuum work clothes after they areworn. Launder them separately. Do not shakeor use
compressed air to removedust from work clothes.
6. WasteDisposal. Disposeof discarded linings, used rags, cloths andHEPA filters with care,
such as in sealed plastic bags. Consult applicableEPA, stateandlocal regulations on waste
disposal.
Regulatory Guidance
References to OSHA, NIOSH, MSHA, andEPA, which areregulatory agencies in theUnited States,
aremade to provide further guidanceto employers andworkers employed within theUnited States.
Employers andworkers employed outside of theUnited States shouldconsult theregulations that
apply to them for further guidance.
NON-ASBESTOS FIBERS WARNING
The followingproceduresfor servicingbrakesare recommendedto reduce exposure to
non-asbestosfiber dust, a cancer andlungdisease hazard. Material Safety Data Sheets
are available from WABCO.
Hazard Summary
Most recently manufactured brakelinings do not contain asbestos fibers. Thesebrakelinings may
contain oneor moreof avariety of ingredients, including glass fibers, mineral wool, aramidfibers,
ceramic fibers andsilicathat can present health risks if inhaled. Scientists disagree on theextent
of therisks from exposureto thesesubstances. Nonetheless, exposureto silicadust can cause
silicosis, anon-cancerous lung disease. Silicosis gradually reduces lung capacity andefficiency
andcan result in serious breathing difficulty. Somescientists believeother types of non-asbestos
fibers, when inhaled, can causesimilar diseases of thelung. In addition, silicadust andceramic
fiber dust areknown to theStateof Californiato causelung cancer. U.S. andinternational
agencies havealso determined that dust from mineral wool, ceramic fibers andsilicaarepotential
causes of cancer.
Accordingly, workers must usecaution to avoidcreating andbreathing dust when servicing brakes.
Specific recommended work practices for reducing exposureto non-asbestos dust follow. Consult
your employer for moredetails.
Recommended Work Practices
1. SeparateWork Areas. Whenever feasible, servicebrakes in aseparatearea away from other
operations to reducerisks to unprotected persons.
2. Respiratory Protection. OSHA has set amaximum allowablelevel of exposurefor silicaof
0.1 mg/m3 as an 8-hour time-weighted average. Somemanufacturers of non-asbestos brake
linings recommendthat exposures to other ingredients foundin non-asbestos brakelinings be
kept below 1.0 f/cc as an 8-hour time-weighted average. Scientists disagree,however, to what
extent adherenceto thesemaximum allowableexposurelevels will eliminatetherisk of disease
that can result from inhaling non-asbestos dust.
Therefore, wear respiratory protection at all times during brakeservicing, beginning with the
removal of thewheels. Wear arespirator equipped with ahigh-efficiency (HEPA) filter approved by
NIOSH or MSHA, if theexposurelevels may exceed OSHA or manufacturers’recommended
maximum levels. Even when exposures areexpected to be within themaximum allowablelevels,
wearing such arespirator at all times during brakeservicing will help minimizeexposure.
3. Procedures for Servicing Brakes.
a. Enclosethebrakeassembly within anegativepressureenclosure. Theenclosureshouldbe
equipped with aHEPA vacuum andworker arm sleeves. With theenclosurein place, usethe
HEPA vacuum to loosen andvacuum residuefrom thebrakeparts.
b. As an alternativeprocedure, useacatch basin with water andabiodegradable,
non-phosphate, water-based detergent to wash thebrakedrum or rotor andother brake
parts. Thesolution shouldbe applied with low pressureto prevent dust from becoming
airborne. Allow thesolution to flow between thebrakedrum andthebrakesupport or the
brakerotor andcaliper. Thewheel hubandbrakeassembly components shouldbe thoroughly
wetted to suppress dust beforethebrakeshoes or brakepads areremoved. Wipethebrake
parts clean with acloth.
c. If an enclosed vacuum system or brakewashing equipment is not available, carefully clean
thebrakeparts in theopen air. Wet theparts with asolution applied with apump-spray bottle
that creates afinemist. Useasolution containing water, and,if available, abiodegradable,
non-phosphate, water-based detergent. Thewheel hubandbrakeassembly components
shouldbe thoroughly wetted to suppress dust beforethebrakeshoes or brakepads are
removed.Wipethebrakeparts clean with acloth.
d. Wear arespirator equipped with aHEPA filter approved by NIOSH or MSHA when grinding or
machining brakelinings. In addition, do such work in an area with alocal exhaust ventilation
system equipped with aHEPA filter.
e. NEVER usecompressed air by itself, dry brushing, or avacuum not equipped with aHEPA
filter when cleaning brakeparts or assemblies. NEVER usecarcinogenic solvents, flammable
solvents, or solvents that can damagebrakecomponents as wetting agents.
4. Cleaning Work Areas. Clean work areas with avacuum equipped with aHEPA filter or by wet
wiping. NEVER usecompressed air or dry sweeping to clean work areas. When you empty vacuum
cleaners andhandleused rags, wear arespirator equipped with aHEPA filter approved by NIOSH
or MSHA, to minimizeexposure. When you replaceaHEPA filter, wet thefilter with afinemist of
water anddisposeof theused filter with care.
5. Worker Clean-Up. After servicing brakes, wash your hands beforeyou eat, drink or smoke.
Shower after work. Do not wear work clothes home. Useavacuum equipped with aHEPA filter to
vacuum work clothes after they areworn. Launder them separately. Do not shakeor use
compressed air to removedust from work clothes.
6. WasteDisposal. Disposeof discarded linings, used rags, cloths andHEPA filters with care,
such as in sealed plastic bags. Consult applicableEPA, stateandlocal regulations on waste
disposal.
Regulatory Guidance
References to OSHA, NIOSH, MSHA, andEPA, which areregulatory agencies in theUnited States,
aremade to provide further guidanceto employers andworkers employed within theUnited States.
Employers andworkers employed outside of theUnited States shouldconsult theregulations that
apply to them for further guidance.

1 Introduction
1
WABCO Maintenance Manual MM-0951 (Revised 08-18)
1 Introduction
Overview
Adaptive Cruise Control
Adaptive Cruise Control (ACC) is an in-vehicle electronic system that
automatically maintains a minimum following interval to a lead
vehicle in the same lane, by controlling engine throttle, engine
retarder or foundation brakes without driver intervention.
Collision Mitigation System
Collision Mitigation System (CMS), if equipped, is integral to the
OnGuard™ Collision Safety System. The system will provide driver
alerts with both a visual and audible alarm through an in-cab dash
display when the vehicles following distance could result in a
rear-end collision. The OnGuard™ Collision Mitigation System will
not become active below 15 mph.
Collision Warning System
The Collision Warning System (CWS) is an in-vehicle electronic
system that monitors the roadway in front of the host vehicle and
warns the driver when a potential collision risk exists at vehicle
speed above 15 mph.
Cruise Control
Cruise Control is the standard system that maintains a vehicle speed
set by the driver.
OnGuard
OnGuard is a collision safety system that incorporates adaptive
cruise control with active braking, CMS, if equipped, and a collision
warning system.
Radar Sensor
The radar sensor is mounted in the front of the vehicle and is used
to detect target vehicles for the OnGuard Collision Safety System.
SAE J1939 Network
The SAE J1939 Serial Control and Communications Vehicle Network
allows various electronic controllers on the vehicle to interact
efficiently and in coordination with each other. The interactions
between controllers include sharing sensor data and calculated
information, allowing subsystems to influence each other’s
operation and communicating subsystem operating state and
configuration.
How OnGuard Works
OnGuard is an Adaptive Cruise Control (ACC) and Collision Warning
System (CWS) and if equipped, a Collision Mitigation System (CMS).
ACC is a radar based tracking system that works in conjunction with
standard Cruise Control to maintain the set cruise speed when no
vehicle is being tracked and maintains a safe following distance
when a target vehicle is being tracked. The safe following distance
is maintained by controlling engine throttle, engine retarder and the
foundation brakes without driver intervention. When the target
vehicle is no longer being tracked, the set cruise speed resumes
automatically.
The CWS provides the driver with an audible and visual alert to a
potentially dangerous driving situation. It is integral with the ACC,
but also functions when the cruise control is not being used. If the
driver is following too close behind another vehicle at a steady
driving speed, the following distance alert emits an audible tone and
the in-cab dash display screen turns yellow. This alert ends when
the driver’s vehicle speed drops below the lead vehicle speed and
the following distance is increased. The alert also activates if the
driver is using the accelerator pedal to override the cruise control
and approaches too close to a vehicle. The CWS and following
distance alert is disabled (will NOT alert) when the driver’s vehicle
speed is below 15 mph.
With the cruise control set, the ACC system provides engine throttle
and retarder control as well as foundation brake activation if
necessary. This automatic brake application is intended only to
provide early braking as the driver is recognizing and reacting to the
situation (the driver must also apply the brakes in response to the
Collision Warning). If the cruise control is not set, the system
provides driver alerts with both visual and audible alarms, but does
not apply braking, engine throttle or retarder control.
The CWS is always active when at a road speed of approximately
15 mph or faster. No action is needed to turn CWS on and it cannot
be arbitrarily turned off. Note, however, that the ACC is only
activated when the cruise control is engaged and functions only
down to the engine manufacturer’s minimum cruise speed.
Collision Mitigation System (CMS) is integral to the OnGuard™
Collision Safety System. The system will provide driver alerts with
both a visual and audible alarm through an in-cab dash display
when the vehicles following distance could result in a rear-end
collision. If a potential rear-end collision is developing and the driver
does not take action to decelerate the vehicle, OnGuard™’s Active
Braking automatically de-throttles the engine, applies the engine
and foundation brakes to provide up to 0.35Gs of braking power.

1 Introduction
2WABCO Maintenance Manual MM-0951 (Revised 08-18)
This Active Braking application is intended only to provide early
braking as the driver is recognizing and reacting to the situation —
the driver must take the appropriate corrective action in response to
the collision warning. The OnGuard™ Collision Mitigation System
will not become active below 15 mph.
WARNING
The OnGuard Collision Safety System should only be
considered an aid to drivers in maintaining a safe following
distance and is not intended to replace driver control over the
vehicle at any time. OnGuard is only intended to initiate
braking of the vehicle in an effort to avoid an incident. It is not
to be relied on to always function and is merely a backup
safety system. In the event the OnGuard Safety System
requires activation of the foundation brakes, there is a limit to
its maximum braking ability (by design). The driver is expected
to intervene and assume control of the braking of the vehicle.
OnGuard should not be relied on to track target vehicles when
either or both vehicles (base and target) have entered and are
traveling through a curve in the road. ACC is not recommended
for use in winding (curving) roads. OnGuard should not be
expected to track smaller objects such as motorcycles,
mopeds, bicycles, etc. OnGuard will not track fixed or
stationary objects.
When operating a vehicle, always use safe driving techniques.
The driver is ALWAYS the most important factor in safe vehicle
operation.
System Components
Radar Sensor
The radar sensor is mounted in the front of the vehicle and centered
in the bumper in most applications. Figure 1.1. The sensor has an
electrical connector that provides power, ground and
communication to the SAE J1939 network which is required for
correct operation.
Figure 1.1
Fascia
The fascia is a protective cover for the radar sensor and is
assembled to the same bracket on which the radar sensor is
mounted. Figure 1.2 and Figure 1.3. The fascia should not be
blocked by any foreign matter (dirt, snow, ice, stickers, etc.),
otherwise a system fault will occur and the OnGuard system will not
operate. There are four styles of fascia to accommodate different
applications. Figure 1.2 and Figure 1.3.
Figure 1.2
Figure 1.1
Figure 1.2
4007298a
RADAR SENSOR
4009027a
CHIN
CHIN

1 Introduction
3
WABCO Maintenance Manual MM-0951 (Revised 08-18)
Figure 1.3
Display
The OnGuard Display provides the interface for the driver.
Figure 1.4. Audible and visual warnings, as well as verification of
correct system operation and faults, are communicated to the
driver. The driver is able to monitor the status of target vehicles that
the OnGuard system is tracking. The functions of the OnGuard
display may be integrated into a vehicle’s architecture/dash display.
If the vehicle has an integrated display, please refer to your owner’s
manual for correct operation.
Figure 1.4
Electrical Harnesses
Several electrical harnesses are required for the OnGuard system.
These include harnesses to connect the radar sensor to power and
ground, as well as the SAE J1939 systems and the OnGuard
Display. The individual harnesses will be detailed throughout this
maintenance manual. Reference to the vehicle manufacturer’s
service manual may also be required to service some of the
electrical harnesses.
Figure 1.3
4009028a
Figure 1.4
4007143a

2 Diagnostics, Troubleshooting and Testing
4WABCO Maintenance Manual MM-0951 (Revised 08-18)
2 Diagnostics, Troubleshooting andTesting
General Information
Radar Sensor and Display Software Levels
Many diagnostic and troubleshooting procedures will require
knowledge of the software level of the OnGuard radar sensor and
display. The software level of these two components can be
determined through the display itself. Figure 2.1. To determine the
software level:
1. Turn the ignition key on and wait for the display to power up.
2. Press the “MODE” button on the display until the screen
labeled “Software Rev” is shown.
Take note of the software version of each component for
reference during the procedures required in this manual and
for component replacement.
Figure 2.1
Fault Codes
If the system is not operating correctly, a fault code may be shown
on the display. Only currently active fault codes are displayed.
Figure 2.2.
NOTE: It is important to document any fault code that is displayed
because stored fault codes are not displayed and are only
retrievable with TOOLBOXTM Software.
NOTE: When active codes are present, the OnGuard system is
disabled. This includes ACC, CWS, CMS and the vehicle cruise
function.
Figure 2.2
Multiple fault codes may be present. If a fault code is shown on the
display, use the UP and DOWN keys on the OnGuard display to scroll
through each fault code. Figure 2.3. Record each code for future
reference.
Figure 2.3
There are two fault code tables in this section. The radar software
version is required to determine which fault code table to use. The
radar software version will be either USO 1.XXXX or USO 2.XXXX.
Figure 2.1. Fault Code Table A is for radar software 1.XXXX. Fault
Code Table B is for radar software USO 2.XXXX.
The Troubleshooting Section and Subsection entries in the far right
column of the Fault Code Tables refer to the more detailed
information provided later on in this manual.
If the display shows a fault code not listed in the Fault Code Tables,
contact WABCO North America Customer Care at 855-228-3203
for assistance.
Figure 2.1
4007300a
SOFTWARE VERSION SCREEN
Display
VO.30
USO2.0016
RadarRadar
SOFTWARE REVSOFTWARE REV
Figure 2.2
Figure 2.3
4007301a
Datalink Not Connected
SPN
SPN
FMI
FMI
Count
Count
2A01 2 26
DM1 Error
DM1 Error
C
o
l
l
i
s
i
o
n
S
a
f
e
t
y
S
y
s
t
e
m
s
OnGuard
TM
MODE
FAULT CODE SCREEN
4007302a
C
o
l
l
i
s
i
o
n
S
a
f
e
t
y
S
y
s
t
e
m
s
OnGuard
TM
MODE
DISPLAY MODE UP/DOWN KEYS

2 Diagnostics, Troubleshooting and Testing
5
WABCO Maintenance Manual MM-0951 (Revised 08-18)
OnGuard fault codes may be generated and displayed during service
procedures on other electrical system components (i.e., engine,
transmission, ABS, etc.). After completion of service on the other
vehicle system components, cycle the ignition OFF for one minute
and then turn the ignition back ON. Start the engine and run it at idle
speed for one minute. This frequently clears the OnGuard fault
code(s).
Troubleshooting Guide
If the OnGuard display does not light up when the engine is on,
make sure that the display brightness is turned up sufficiently to
make the screen visible. If the display brightness adjustment is
correct or the adjustment screen cannot be seen, the display is not
receiving any power or input signals. This can be caused by
problems in the electrical harness. Refer to Display Harness
Electrical Checks in the Electrical System and Harness
Troubleshooting Section.
OnGuard fault codes may be generated and displayed during service
procedures on other electrical system components (i.e., engine,
transmission, ABS, etc.). If the OnGuard display screen turns red
with fault codes visible after the vehicle has been serviced for other
vehicle system issues, cycle the ignition OFF for one minute, turn
the ignition back ON, start the engine and run at idle speed for one
minute. This frequently clears the OnGuard fault code(s).
If the OnGuard Collision Safety System is not correctly tracking
vehicles that are in your lane or is tracking vehicles that are not in
your lane, this may be due to radar operational issues.
Typically these are radar operational issues that can result from the
following problems:
앫Debris (dirt, snow, ice) on the radar fascia or between the fascia
and the radar sensor. This must be cleaned off.
앫The radar fascia may be mounted upside down. The radar fascia
should be mounted with the indented “chin” positioned facing
the radar electrical connector location.
앫The radar sensor may be loose or not tightly secured on the
alignment screws. Check that the alignment screws are turned in
so that the gap between the radar sensor and the mounting
bracket is 1/4 to 3/8 inch. Also check that the radar sensor
alignment screws are seated in the ball socket clips and the ball
socket clips are fully seated in the radar sensor. Verify that the
ball socket clips and through-hole adjusters are not broken.
Adjust, repair and replace the alignment screws, ball socket clips
and through-hole adjusters as necessary.
앫The radar sensor may be too close to or actually contacting the
bumper as mounted, which will affect the radar signal. There
should be at least 1/4 inch of clearance between the fascia,
radar sensor or bracket and the bumper. Check that the
adjustment screws are turned in so that the gap between the
radar sensor and the mounting bracket is 1/4 to 3/8 inch. If this
does not resolve the problem of the fascia or radar sensor
touching the bumper, contact your vehicle manufacturer
representative on adjustments to the bumper for radar sensor
clearance.
앫The radar may not be aligned correctly. Refer to the Radar
Sensor Alignment procedure.
If the OnGuard display is showing a red screen with the message
“ACC1 Link Error”, Figure 2.4, this screen means that the display
isn’t receiving SAE J1939 network messages from the radar sensor.
This can be caused by problems in the electrical harness. Refer to
Radar Harness Electrical Checks in the Electrical System and
Harness Troubleshooting Section.
Figure 2.4
If the OnGuard display shows a red screen with the message “Mode
6 Error”, Figure 2.5, this screen means that the display cannot
process error messages that it is receiving from the radar. Replace
the display per the Display Replacement procedure in Section 3.
Figure 2.4
4007150a
DATA ERROR
ACC1 Link Error

2 Diagnostics, Troubleshooting and Testing
6WABCO Maintenance Manual MM-0951 (Revised 08-18)
Figure 2.5
If the vehicle’s standard cruise control is working and OnGuard
Adaptive Cruise Control (ACC) is not working, consult your dealer or
engine supplier. This can occur if the engine controller has been
re-programmed or the engine parameter that activates OnGuard has
been turned off. Consult with your dealer or engine supplier for
engine software and parameter adjustments.
If the OnGuard display shows a red screen with a fault code, refer to
Table A for Software Version USO 1.XXXX or Table B for Software
Version USO 2.XXXX for a description. Also refer to the
Troubleshooting Section and Sub-Section of this manual, listed in
the last column of Table A or Table B.
NOTE: Be sure to scroll through all active faults using the display
UP and DOWN arrow keys.
The Fault Code Screen shown in Figure 2.2 will typically be a one or
two line fault description, an SPN error code, an FMI and a count.
Look up the error code number in column one of the Fault Code
Tables and find the repair instructions. Refer to Table A for Software
Version USO 1.XXXX or Table B for Software Version USO 2.XXXX.
TOOLBOX Software Diagnostics
Figure 2.6
NOTE: TOOLBOX™ Software version 10.0 or higher.
NOTE: For installation and setup instructions for using TOOLBOX™
Software, refer to the TOOLBOX™ Software User’s Manual,
TP-99102. The manual is posted on wabco-auto.com/TOOLBOX.
To access the WABCO TOOLBOX™ Software from the desktop
screen, double-click on the WABCO PC Diagnostics (TOOLBOX™)
icon. Figure 2.7.
Figure 2.7
From the message box that appears, click on the OnGuard Radar
Diagnostics button. Figure 2.8.
Figure 2.8
Figure 2.5
Figure 2.6
4007303a
MODE 6 ERROR
DATA ERROR
Mode 6 Error
4007045a
Figure 2.7
Figure 2.8
4008868a
4008869b
WABCO Toolbox PC Diagnostics

2 Diagnostics, Troubleshooting and Testing
7
WABCO Maintenance Manual MM-0951 (Revised 08-18)
Displaying Radar Information:
To retrieve radar sensor information, select “Diagnostic Information”
from the OnGuard Radar Diagnostics home screen. Figure 2.9.
Figure 2.9
This will then display the radar sensor part number and software
levels, as well as other important information. Figure 2.10.
Figure 2.10
Retrieving Faults:
1. To display OnGuard radar sensor faults, select the “Display”
option from the menu.
2. From the pull-down menu, select “Diagnostic Trouble Codes”
to bring up the fault information screen. Figure 2.11.
Figure 2.11
Figure 2.9
Figure 2.10
4008870a
WABCO OnGuard Radar Diagnostics
4008871a
Figure 2.11
4008872a

2 Diagnostics, Troubleshooting and Testing
8WABCO Maintenance Manual MM-0951 (Revised 08-18)
3. A description of the fault, the number of times the fault
occurred, the suspect parameter number (SPN) and the failure
mode identifier (FMI) are all displayed in the Diagnostic Trouble
Codes window. Basic repair instructions for each fault are also
provided. Figure 2.12. After making the necessary repairs, use
the “Clear Faults” button to clear the faults.
Figure 2.12
4. A fault report can also be generated by selecting the “Generate
Fault Report “button, while in the “Diagnostic Trouble Codes”
screen. A “Save As” screen will then come up asking you to
name the file and select where it will be saved. Figure 2.13.
The “Fault Report” screen provides additional information that
is not included in the “Diagnostic Trouble Codes” screen.
Figure 2.14.
Figure 2.13
Figure 2.14
Faults can be cleared after generating a fault report. Only
stored faults will clear. Figure 2.12.
Recording OnGuard J1939 Data:
1. To access OnGuard Radar J1939 Data, click on “J1939 Bus
Data” from the OnGuard Radar Diagnostics home screen.
Figure 2.9.
Figure 2.12
4008873a
Figure 2.13
Figure 2.14
4008874a
4008875b

2 Diagnostics, Troubleshooting and Testing
9
WABCO Maintenance Manual MM-0951 (Revised 08-18)
2. To capture a log file, click on “Start Logging”. Figure 2.15. A
single log file will capture up to 5 minutes of information. To
pause a log file, click on “Pause”; to resume logging, click on
“Resume”. Once the required data has been captured, click on
“Stop Logging”. Figure 2.16.
Figure 2.15
Figure 2.16
3. A “Save As” screen will then come up asking you to name the
file and select where it will be saved. Figure 2.17. Specific
messages can also be viewed after saving the file by clicking
on “Load Saved Data”, and then highlighting the desired
message. Figure 2.18.
Figure 2.17
Figure 2.18
Figure 2.15
Figure 2.16
4008877a
4008878a
Figure 2.17
Figure 2.18
4008879a
4008880a

2 Diagnostics, Troubleshooting and Testing
10 WABCO Maintenance Manual MM-0951 (Revised 08-18)
Displaying Application Parameters:
1. Certain specific radar application parameters can be viewed
and reset using TOOLBOX™ Software. To access this screen,
select the “Display” option from the menu.
2. From the pull-down menu, select “Application Parameters” to
bring up the “Application Parameters” screen. Figure 2.19.
Figure 2.19
3. The Application Parameters screen will then appear. Driveline
Retarder, Transmission Type, Air Suspension Front Axle and Air
Suspension Rear Axle can all be reset by clicking on “Reset
Application Parameters.” Figure 2.20.
Figure 2.20
4. If the radar software version is USO 1.XXXX, these parameters
cannot be reset. A message will then be displayed on the
screen explaining this. Figure 2.21.
Figure 2.21
Figure 2.19
4008881a
Figure 2.20
Figure 2.21
4008882a
4008918a

2 Diagnostics, Troubleshooting and Testing
11
WABCO Maintenance Manual MM-0951 (Revised 08-18)
5. If the radar software version is USO 2.XXXX, a message will be
displayed to show that the parameters have been changed.
Figure 2.22. Note that changed parameters are shown in red
and the state of CMS cannot be changed. Figure 2.23.
Figure 2.22
Figure 2.23
6. If the radar software version is USO 2.0026 or higher, the
parameters for “Air Suspension Front Axle” and “Air
Suspension Rear Axle” are not available. Figure 2.24.
Figure 2.24
Figure 2.22
Figure 2.23
4008919a
4008920a
Figure 2.24
4008921a

2 Diagnostics, Troubleshooting and Testing
12 WABCO Maintenance Manual MM-0951 (Revised 08-18)
Radar Software Version USO 1.XXXX
Fault Code Table
This fault code table is for use with radar sensors that have release
USO 1.XXXX software only. Refer to the section Radar Sensor and
Display Software Levels to determine the software level. If the
display shows a fault code not listed in the table, contact WABCO
North America Customer Care at 855-228-3203 for assistance.
Table A: Radar Software Version USO 1.XXXX Fault Code Table
Fault Code
SPN/FMI
Displayed
Description Fault Description Repair Instructions
Troubleshooting
Section
Sub-Section
2A00/02 Datalink Not
Connected
J1939 network bus
connection error after several
restarts at 0.02s, 0.2s, 2.0s
and 20s
앫Verify J1939 network bus termination
resistors are installed at both ends of the
backbone.
앫Verify all ECUs on the J1939 network bus are
transmitting at 250 Kbits/sec.
Radar Harness
Troubleshooting
2A01/02 Datalink Not
Connected
No J1939 network messages
received at all
앫Verify J1939 network is connected to each
component.
앫Verify J1939 Hi and Lo connections are not
reversed on any component on the network.
앫Verify J1939 network bus termination
resistors are installed at both ends of the
backbone.
앫Verify J1939 bus resistance is 60 ohms from
J1939 Hi to J1939 Lo.
앫Verify all ECUs on the network are transmitting
at 250 Kbits/sec.
Radar Harness
Troubleshooting
2A01/22 Radar Memory
Error
Radar horizontal alignment
error or yaw rate sensor
invalid signal
앫Verify condition of radar mounting and
hardware.
앫Realign radar sensor using alignment
procedure.
앫Check display for number of fault occurrences.
앫If none of the above resolves the issue,
contact WABCO North America Customer Care
at 855-228-3203 for further assistance.
Radar System
Radar Sensor
Alignment
2A01/24 Unlisted DM1 Error Undefined Error 앫If this error occurs, contact WABCO North
America Customer Care at 855-228-3203 for
further assistance.
Radar System

2 Diagnostics, Troubleshooting and Testing
13
WABCO Maintenance Manual MM-0951 (Revised 08-18)
2A02/02 Cruise Control
Msg Timeout
CCVS message timeout >
5 messages
앫Verify engine ECU is functional and has correct
parameters and software downloaded from
the engine database.
앫Verify the correct engine ECU part number is
used on this vehicle.
앫Cycle the ignition to clear faults after engine
servicing.
Component
Message Fault
Message Timeout
2A02/22 Unlisted DM1 Error Radar alignment error 앫Realign radar using sensor alignment
procedure.
Radar System
Radar Sensor
Alignment
2A03/02 Cruise Control
Data Error
Invalid parking brake switch
signal CCVS message
앫Use the OnGuard display “ACC FUNCTION”
screen to determine if the parking brake
switch is operational.
앫Verify engine ECU is functional and has correct
parameters and software downloaded from
the engine database.
앫Verify the correct engine ECU part number is
used on this vehicle.
앫Cycle the ignition to clear faults after engine
servicing.
Component
Message Fault
Message Data
Error
2A04/02 Cruise Control
Data Error
Invalid BRAKE_SWITCH
signal CCVS message
앫Use the OnGuard “ACC FUNCTION” screen to
determine if brake switch is operational.
앫Verify engine ECU is functional and has correct
parameters and software downloaded from
the engine database.
앫Verify the correct engine ECU part number is
used on this vehicle.
앫Cycle the ignition to clear faults after engine
servicing.
Component
Message Fault
Message Data
Error
2A07/02 Brake Control Data
Error
Invalid front axle speed signal
in EBC2 message
앫Verify ABS ECU is functional.
앫Verify the correct ABS ECU part number is
used on this vehicle.
앫Cycle the ignition to clear faults after ABS
servicing.
Component
Message Fault
Message Data
Error
Fault Code
SPN/FMI
Displayed
Description Fault Description Repair Instructions
Troubleshooting
Section
Sub-Section
Table A: Radar Software Version USO 1.XXXX Fault Code Table

2 Diagnostics, Troubleshooting and Testing
14 WABCO Maintenance Manual MM-0951 (Revised 08-18)
2A0A/00 Radar Blocked or
Dirty
Radar signal attenuation. No
target vehicle detected with
vehicle moving > 6 mph
(10 km/h)
앫Determine if radar sensor is blocked by snow,
ice or dirt.
앫Clean surface of fascia and between fascia
and radar sensor.
앫Verify correct fascia is installed correctly.
Radar System
Radar Blocked
2A0A/02 Brake Control Data
Error
Invalid brake pedal position %
signal in EBC1 message
앫Use OnGuard display “ACC FUNCTION” screen
to verify brake pedal position (BPP) sensor is
operational.
앫ABS ECU is functional.
앫Verify the correct ABS ECU part number is
used on this vehicle.
앫Inspect BPP sensor harness for damage.
앫Verify BPP sensor connector is secured.
앫Check for debris, ice, water, oil, etc., in air
system.
앫Replace BPP sensor if required.
앫Replace ABS ECU if required.
ABS System
Brake Pedal
Position (BPP)
Sensor Fault
2A0A/23 Unlisted DM1 Error Internal radar voltage issue 앫Cycle the ignition several times, waiting for the
display to turn from a red screen to the blue
vehicle screen after several ignition cycles.
앫Verify correct system operation.
앫If the error occurs again after multiple ignition
cycles, contact WABCO North America
Customer Care at 855-228-3203 for further
assistance.
Radar System
Radar Multiple
Reset Fault
2A0B/00 Radar Blocked or
Dirty
No target detected for
2 minutes with vehicle
moving > 6 mph (10 km/h)
앫Determine if radar sensor is blocked by snow,
ice or dirt.
앫Clean surface of fascia and between fascia
and radar sensor.
앫Verify correct fascia is installed correctly.
Radar System
Radar Blocked
2A0B/23 Unlisted DM1 Error Internal Radar Voltage Issue 앫Cycle the ignition several times, waiting for the
display to turn from a red screen to the blue
vehicle screen after several ignition cycles.
앫Verify correct system operation.
앫If the error occurs again after multiple ignition
cycles, contact WABCO North America
Customer Care at 855-228-3203 for further
assistance.
Radar System
Radar Multiple
Reset Fault
Fault Code
SPN/FMI
Displayed
Description Fault Description Repair Instructions
Troubleshooting
Section
Sub-Section
Table A: Radar Software Version USO 1.XXXX Fault Code Table

2 Diagnostics, Troubleshooting and Testing
15
WABCO Maintenance Manual MM-0951 (Revised 08-18)
2A0C/02 Cruise Control
Data Error
Invalid clutch switch signal in
CCVS message
앫Use OnGuard display “ACC FUNCTION” screen
to verify Clutch Switch is operational.
앫Verify correct radar sensor is installed in
vehicle.
앫If manual transmission radar sensor is
installed in auto transmission vehicle, fault will
occur.
Component
Message Fault
Message Data
Error
2A19/02 Transmission
Control Data Error
Invalid driveline engaged
signal in ETC1 message
앫Use OnGuard display “ACC FUNCTION” screen
to verify Driveline Engage is operational.
앫Verify transmission ECU is functional and has
correct parameters and software.
앫Verify the correct transmission ECU part
number is used on this vehicle.
앫Cycle the ignition to clear faults after
transmission servicing.
Component
Message Fault
Message Data
Error
2A26/02 Brake Control Msg
Timeout
EBC1 message timeout >
5 messages
앫Verify that ABS ECU is connected to the J1939
network.
앫Verify J1939 network operational.
앫Verify correct ABS part number is used.
앫Cycle the ignition to clear faults after ABS
servicing.
Component
Message Fault
Message Timeout
2A28/02 Engine Control
Msg Timeout
EEC1 message timeout >
5 messages
앫Verify engine ECU is functional and has correct
parameters and software downloaded from
the engine database.
앫Verify the correct engine ECU part number is
used on this vehicle.
앫Cycle the ignition to clear faults after engine
servicing.
Component
Message Fault
Message Timeout
2A29/02 Engine Retarder
Control Msg
Timeout
ERC1ER message timeout >
5 messages
앫Verify engine ECU is functional and has correct
parameters and software downloaded from
the engine database.
앫Verify the correct engine ECU part number is
used on this vehicle.
앫Cycle the ignition to clear faults after engine
servicing.
Component
Message Fault
Message Timeout
Fault Code
SPN/FMI
Displayed
Description Fault Description Repair Instructions
Troubleshooting
Section
Sub-Section
Table A: Radar Software Version USO 1.XXXX Fault Code Table

2 Diagnostics, Troubleshooting and Testing
16 WABCO Maintenance Manual MM-0951 (Revised 08-18)
2A38/02 Engine Control
Data Error
Invalid actual percent torque
signal in EEC1 message
앫Verify engine ECU is functional and has correct
parameters and software downloaded from
the engine database.
앫Verify the correct engine ECU part number is
used on this vehicle.
앫Cycle the ignition to clear faults after engine
servicing.
Component
Message Fault
Message Data
Error
2A40/02 Engine Control
Data Error
Invalid engine speed signal in
EEC1 message
앫Verify engine ECU is functional and has correct
parameters and software downloaded from
the engine database.
앫Verify the correct engine ECU part number is
used on this vehicle.
앫Cycle the ignition to clear faults after engine
servicing.
Component
Message Fault
Message Data
Error
2A43/02 Brake Control Msg
Timeout
EBC2 timeout > 5 messages 앫Verify that ABS ECU is connected to the J1939
network.
앫Verify J1939 network operational.
앫Verify correct ABS part number is used.
앫Cycle the ignition to clear faults after ABS
servicing.
Component
Message Fault
Message Timeout
2A44/02 Power Supply
Undervoltage
Vehicle voltage to radar <
6 VDC
앫Verify that the voltage at the radar sensor is >
6 VDC when loaded with a headlamp
connected across pins 1 and 6 of the radar
sensor connector.
앫Inspect the radar connector for corrosion.
앫Inspect each of the power connections
between the ignition switch and the radar to
determine where loss of power may be
occurring.
Electrical System
and Harnesses
System Voltage
Fault
2A45/02 Power Supply
Overvoltage
Vehicle voltage to radar >
16 VDC
앫Monitor the battery voltage to determine if the
battery is providing voltage between 10V and
16V.
앫If the voltage exceeds 16V, troubleshoot the
voltage regulator and alternator system.
앫Also determine if a jump start or battery
charging has occurred that could cause a
vehicle overvoltage condition.
Electrical System
and Harnesses
System Voltage
Fault
Fault Code
SPN/FMI
Displayed
Description Fault Description Repair Instructions
Troubleshooting
Section
Sub-Section
Table A: Radar Software Version USO 1.XXXX Fault Code Table