august2022 - 12

" Many of these systems have radar-based sensors
in the bumper and cameras in the cab, " said Ben
Murphy, associate VP of equipment resources
at Werner. " They need to be rugged and rigid
to withstand the stress associated with rolling
down the highway.
" Understanding how to react if one of the
systems is out of sync is essential, " Murphy
continued. " Buy-in from drivers and including
them during the testing and validation processes
is important when you decide to start using
ADAS technologies. At the same time, they need
to understand the importance, from a service
perspective, to provide feedback about notifications
they receive in the cab. "
A key part of the service process for Werner is
an alert system that is based on exceptions. " It
is unrealistic to scroll through data for all these
trucks daily to find unique examples of notifications,
so we look to manufacturers to provide
exception-based reports, " Murphy said.
» Maintenance management software also plays a role in preventive and
predictive service practices for ADAS and other safety technologies.
Photo: Trimble Transportation
Stocking up on parts
One of the biggest challenges Werner currently
faces is the need to have inventory on hand,
and in the right locations, for repairs. To address
supply chain issues, the fleet works ahead with its
providers to understand their needs and have the
necessary parts available. This mutually beneficial
partnership with manufacturers also allows
the ability to make regular upgrades to diagnostic
software over the life of the technology.
A solid vendor network is important as well. " We
can't solely rely on our network of company shops
because some of our trucks may not reach one
of those facilities when a service event or repair
Stability technology and the
need for maintenance, training
Along with ADAS, modern tractor-trailers
are also often equipped
with stability technology to prevent
a disastrous roll-over event by
adjusting when each set of brakes
activate. Stability systems have
been mandated since 2017 on new
heavy-duty tractors, and the technology
is prevalent on trailers as
well. Several components must work
in concert to keep a fully-loaded
tanker from tipping on an icy road,
so technicians must be fully aware
of how those interactions play
out and how to diagnose issues.
In May, Brian Screeton, Bendix
technical service training supervisor,
held an in-depth session
at the company headquarters in
Avon, Ohio, to help techs understand
what each component
of the Bendix ESP (Electronic
Stability Program) full stability
system does and how to troubleshoot
some common issues.
" There is not much maintenance
required unless there have been
adjustments or repairs done to the
chassis, such as chassis alignment
or any steering or suspension
system repair, " Screeton noted. " In
these cases, calibration of the steering
angle sensor would be required. "
One area he discussed that could
confound troubleshooters is the
yaw rate/lateral acceleration sensors
(YRS). These sensors help detect an
oversteering event that could cause
a rollover. They work in conjunction
with the ABS system, wheel speed
sensors, and steering angle sensors,
all of which are processed by the
ECU. The system will then intervene
if corrective action is required.
Some steps to diagnose an issue
include: verifying proper installation
and the correct YRS model is used,
checking the wiring from the sensor
to ECU, and ensuring that the
sensor is securely mounted and not
moved from its original location.
Techs must also be trained on how
to correctly use the system's diagnostic
tools. Bendix safety systems
all require the Bendix ACom Pro
diagnostic software. In general,
Screeton recommended drivers are
well-versed in operation as well.
" With any safety system, the shops
and fleets need to make the proper
training of their drivers and technicians
a priority, " Screeton said.
" This will help the drivers explain
any issues to the technicians
accurately, and they will also know
what to expect when the system
may intervene. The technicians
need a good understanding of
how the system works and also of
the correct diagnostic tools to be
able to effectively maintain and
diagnose any issues that may arise. "
-John Hitch
» An example of when Bendix' ESP is turned off...
and when it is working.
Photos: Bendix Commercial Vehicle Systems
12 Fleet Maintenance | August 2022
august2022

Table of Contents for the Digital Edition of august2022
