14
Truck Chassis Modifications
If the vehicle’s chassis components are altered (for example,
a wheel base extension or reduction, tag axle addition
or removal, a major body change such as conversion of
a tractor into a truck, or an axle, suspension, or steering
system component modification) the Bendix
®
ESP
®
system
must be disabled. Have a qualified mechanic replace the
Advanced EC-60 ECU with a Premium EC-60 ECU and
secure the X4 connector which will no longer be used. The
ATC/ESP indicator lamp would continue to function as an
ATC indicator lamp, and should be designated as ATC only.
WARNING
: If a modified vehicle does not have
the ESP system disabled, serious vehicle braking
and performance issues could result, including
unnecessary ESP system interventions . This can
lead to a loss-of-control of the vehicle . In addition,
remove all cab signage (e .g . visor labels, etc .) used
to show that Bendix ESP was installed and make any
necessary notations in the vehicle manual(s), so that
drivers do not misunderstand which ABS options are
installed on the vehicle .
Sensor Location Modifications
The location and orientation of the Steering Angle Sensor
and Yaw Rate Sensor must not be altered. When servicing,
an identical component must be used in the same
orientation (using OEM brackets & torque requirements).
During installation follow the OEM leveling guidelines.
Steering Angle Sensor Re-Calibration
Whenever maintenance or repair work is performed to the
steering mechanism, linkage, steering gear, adjustment of
the wheel track, or if the steering angle sensor is replaced,
a recalibration of the Steering Angle Sensor must be
performed.
WARNING
! If the Steering Angle Sensor is not
recalibrated, the yaw control system may not function
properly, which can result in incidents leading to loss
of vehicle control . See page 19 of this document for
more details on this procedure .
DYNAMOMETER TEST MODE
CAUTION
:
ATC and ESP must be disabled prior
to conducting any dynamometer testing. When the
Dynamometer Test Mode is engaged, ATC brake control
and engine control along with drag torque control and ESP
are turned off. This test mode is used to avoid torque
reduction or torque increase and brake control activation
when the vehicle is operated on a dynamometer for testing
purposes.
The Dynamometer Test Mode may be activated by pressing
and releasing the diagnostic blink code switch five times or
by using a hand-held or PC-based diagnostic tool.
During Dynamometer Test Mode the ATC lamp remains ON.
Advanced Bendix
®
EC-60
™
Contollers will remain engaged
in the Dynamometer Test Mode even if power to the ECU
is removed and re-applied. To exit the test mode, press
and release the blink code switch three times, or use a
hand-held or PC-based diagnostic tool.
AUTOMATIC TIRE SIzE CALIBRATION
The ECU requires a precise rolling circumference ratio
between steer axle and drive axle tires in order for ABS,
ATC, and ESP to perform in an optimal manner. For this
reason, a continuously monitoring process takes place
in which the precise ratio is calculated. This calculated
value is stored in the ECU memory provided the following
conditions are met:
1. Rolling-circumference ratio is within the permissible
range.
2. Vehicle speed is greater than approximately 12 MPH.
3. No acceleration or deceleration is taking place.
4. There are no active speed sensor diagnostic trouble
codes.
The ECU is provided with a ratio value of 1.00 as a default
setting. If the automatic tire size alignment calculates a
different value, this is used to overwrite the original figure
in the memory. This process adapts the ABS and ATC
function to the vehicle.
Acceptable Tire Sizes
The speed calculation for an exciter ring with 100 teeth is
based on a default tire size of 510 revolutions per mile.
This figure is based on the actual rolling circumference of
the tires, which varies with tire size, tire wear, tire pressure,
vehicle loading, etc.
The ABS response sensitivity is reduced when the actual
rolling circumference is excessive on all wheels. For a 100
tooth exciter ring, the minimum number of tire revolutions
per mile is 426, and the maximum is 567. The ECU will
set diagnostic trouble codes if the number of revolutions
is out of this range.
