Bendix Commercial Vehicle Systems EC-60 ATC STD/PREM CONTROLLERS - Manual (Page 8)

8
Disabling ATC Differential Braking
ATC differential braking is disabled under the following
conditions:
1. During power up (e.g. when the vehicle is started), until
the ECU detects a service brake application.
2. If the ECU receives a J1939 message indicating that
the vehicle is parked.
3. When the dynamometer test mode is active. The
dynamometer test mode is entered using the diagnostic
blink code switch or by using a diagnostic tool (such as
Bendix ® ACom ® Diagnostics).
4. In response to a serial communications request from
a diagnostic tool.
5. During brake torque limiting to avoid overheating of the
brakes.
6. When certain diagnostic trouble code conditions are
detected.
Engine Torque Limiting (ETL) with Smart ATC ™
Traction Control
The EC-60 ™ controller uses Engine Torque Limiting to
control drive axle wheel slip. This is communicated to the
engine control module (using J1939), and is available at
all vehicle speeds.
Bendix ® Smart ATC ™ Traction Control
The EC-60 ™ controller has an additional feature known as
Smart ATC ™ traction control. Smart ATC ™ traction control
monitors the accelerator pedal position (using J1939) to
help provide optimum traction and vehicle stability. By
knowing the driver’s intention and adapting the target
slip of the drive wheels to the driving situation, the Smart
ATC ™ traction control allows higher wheel slip when the
accelerator pedal is applied above a preset level.
The target wheel slip is decreased when driving through a
curve for improved stability.
Disabling ATC Engine Control and Smart ATC
™ Traction
Control
ATC Engine Control and Smart ATC
™ traction control will
be disabled under the following conditions:
1. In response to a serial communications request from
an off-board tool.
2. At power-up until the ECU detects a service brake
application.
3. If the ECU receives a J1939 message indicating that
the vehicle is parked.
4. If the dynamometer test mode is active. This may be
accomplished via an off-board tool or the diagnostic
blink code switch.
5. When certain diagnostic trouble code conditions are
detected.
Optional ATC Off-Road Mode
In some road conditions, the vehicle operator may desire
additional drive wheel slip when ATC is active. The
Premium EC-60 ™ controller has an optional control mode
to permit this desired performance.
The vehicle operator can activate the off-road function with
a switch on the dash panel. Alternately, a J1939 message
may be used to place the vehicle in this mode. The ATC
Indicator Lamp will flash continually to confirm that the
off-road ATC function is engaged.
To exit the ATC off-road mode, depress and release the
ATC off-road switch.
Drag Torque Control Functional Overview
Premium EC-60 ™ controllers have a feature referred to as
drag torque control which reduces wheel slip on a driven
axle due to driveline inertia. This condition is addressed
by increasing the engine torque to overcome the inertia.
Drag torque control increases vehicle stability on low-
traction road surfaces during down-shifting or retarder
braking.
DYNAMOMETER TEST MODE
WARNING: ATC must be disabled prior to conducting
any dynamometer testing. When the Dynamometer Test
Mode is enabled, ATC brake control and engine control
along with drag torque control 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 purpose.
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.
The Dynamometer Test Mode will remain active even if
power to the ECU is removed and re-applied. Press and
release the blink code switch three times, or use a hand-
held or PC-based diagnostic tool to exit the test mode.