2
Building Blocks Pyramid of Safety
Complete Brake System Integration
Safety Systems On-Board Vehicles
ABS, ATC, RSC, RSS, OnGuard
.
Anti-Lock Braking System (ABS)and
Automatic Traction Control (ATC)
Accelerometer
Cab Frame
Accelerometer
ABS / ECU With RSC Accelerometer
COLOR KEY
Primary
Secondary
Park & Emergency
Blended Air
Supply
Electrical Wire
Roll Stability Control
Roll Stability Control (RSC) Platform
• RSC functionality integrated in power unit ABS / ATC ECU– Accelerometer mounted directly to ECU Printed Circuit Board
• When roll thresholds are exceeded:– SAE J1939 datalink used to de-throttle engine & apply engine
brake / retarder
– Solenoid valves can actuate steer, drive & trailer axle brakes
• SAE J1587 and J1939 DataLink for driver communication & diagnostics
• Stability / ATC indicator lamp
• Measurement & processing of lateral acceleration
• Calculation of critical acceleration limit
• Rollover risk detection
• RSC intervention
hcog
COG
Flat
GR
Flat
G
S
Functional Elements of RSC
•Engine control•Retarder control•Brake control
• Closed loop control
• Type and magnitude of intervention determined by relationship of measured relevant lateral acceleration to control critical acceleration limit
• ATC/RSC light on in dash during event
• Intervention always includes engine torque reduction, followed by application of• Engine brake (if equipped)
• Drive axle and trailer brakes
RSC Intervention
Warning Light on Dash
RSC Indicator Lamp-ATC Lamp
Roll Stability Intervention (Stage One-Throttle)
Roll Stability Intervention (Stage 2 Engine Brake)
Roll Stability Intervention (Stage 3, Apply Brakes
OnGuard Collision Safety SystemUses forward-looking 77 Ghz radar sensor technology to monitor distance to target vehicle
Integrates collision safety
system control with ABS and
stability control.
•Screen background color–Blue: standby mode no target vehicle detected
–Green: target vehicle detected
–Yellow: following distance alert
–Red: collision warning
OnGuard™ Display
• Radar - 77 ghz• Radar sensor transmitter
broadcast high frequency radio signals
• Radio signals bounce off objects and return to receiver
• Determines speed and distance of target
OnGuard™ Radar Sensor
Fascia
Connector DownConnector Up
19
Cruise Control NOT Set:
CMS is always activated at speeds above 15 mph and will apply brakes and engine retarder control, as well as audible and visual alerts if the situation requires it.
System on and Cruise Control not set. No lead vehicle detected.
System on and Cruise Control not set. Lead vehicle detected.
Following Distance Alert Lead vehicle is within safe following range.
20
Cruise Control Set:
You activate the cruise control speed using factory cruise controls. When a vehicle is detected in front of you the system controls your speed to maintain a set distance between you and the detected vehicle. The CWS is on and will emit visual and audible collision warnings and if there is a collision event will APPLY BRAKING, ENGINE OR RETARDER CONTROL if needed.
System on and Cruise Control set. No lead vehicle detected.
System on and Cruise Control set. Lead vehicle detected. You may sense a decrease in power or vehicle speed in order to maintain a set distance between you and the detected vehicle.
The braking, engine and retarder control may
activate, and reduce the vehicle speed. The driver should also initiate braking if needed.
21
Fault Codes, OnGuard Disabled
Diagnostics
Adaptive Cruise Control (ACC)NO VEHICLE AHEAD
65 MPH
55 MPH
VEHICLE DETECTED
AHEAD
65 MPH to
55 MPH
55 MPH
55 MPH
55 MPH
Driving at a Set Speed
Vehicles Not in Lane Rejected
1. Constant Speed Driving1. Constant Speed Driving 2. Deceleration Control2. Deceleration Control
Speed Reduced From
65 MPH to 55 MPH
3. Tracking Control3. Tracking Control
Minimum Set Following
Distance Maintained
Set Following
Distance
55 MPH to
65 MPH
55 MPH
VEHICLE
CHANGES
LANES
55 MPH to
45 MPH
65 MPH to
45 MPH
45 MPH
to 65 MPH
6. Changing Lanes6. Changing Lanes
45 MPH
Driver Changes Lanes & Uses Turn
Signal – Speed Increased to 65 MPH
4. Acceleration Control4. Acceleration Control
Speed Increased from
55 MPH Back to 65 MPH
5. Deceleration Control5. Deceleration Control
Speed Reduced From 55 MPH to
45 MPH Using Throttle, Engine Brake
and Tractor Foundation Brakes
VEHICLE CUTS IN
AND SLOWS
55 MPH
New Lead Vehicle
detected, significantly
inside set following
distance
Vehicle ahead out of
lane & disregarded,
no lead vehicle
assigned
65 MPH to
55 MPH
9. Disengagement9. Disengagement
Driver Actuates Brake Pedal
to Disengage
7. Roll Control7. Roll Control
65 MPH to
50 MPH
ACC Yaw Rate Sensor Senses
Excessive Lateral “G” Forces
and Throttles Engine Down
65 MPH to
50 MPH
8. Bend Adjustment8. Bend Adjustment
Lead Vehicle
Non-Lead Vehicle
ACC Yaw Rate Sensor
adjusts detection zone for
turn
Diagnostics
•Performed via the OnGuard display. (Active Faults Only).
•TOOLBOX Software 10.0 capable of diagnosing radar sensor faults and other data.
Diagnostics: Fault Codes, OnGuard disabled
Toolbox Software Diagnostics
Toolbox Software Diagnostics
Toolbox Software Diagnostics
Toolbox Software Diagnostics
Diagnostic Fault Codes USO 2.XXXX
SPN/FMI Displayed Description
Repair Instructions
86110 / 12 Radar Init Error Verify no foreign objects on radar.
86416 / 13 Yaw Offset or H Align Error
Check radar mounting and alignment.
86516 / 14 Radar Blocked or Align Verify no foreign objects on radar. Check mounting & align.
86517 / 14 Radar Blocked or Align Verify no foreign objects on radar. Check mounting & align.
86566 / 12 Engine Ignores ACC Control
Usually a secondary fault.
Radar Inspection• Inspect the bumper, and fascia for any damage.
• Verify there is at least ¼” of clearance between the fascia and bumper.
• Remove fascia (either 7/16” bolts, or T-30), verify there is at least ¼” of clearance between the radar and the bumper.
• Verify connector is fully plugged in, and there is no damage to it, or the rubber boot.
• Inspect all three screws and clips, make sure not broken and screws are fully engaged.
• Hold both sides of radar and wiggle (should not be any play).
Radar Inspection
Radar Removal
• Remove fascia (either 7/16” bolts, or T-30).
• Press on the locking tabs, and remove the electrical connector.
• Use a T-20 torx bit and ratchet and carefully remove all three radar screws.
• Once radar is removed, inspect all three screws and clips. Inspect the three through hole adjusters. Make sure they are tight and not damaged.
• Inspect the radar harness and radar connector for damage and corrosion.
• Note: if there is any damage, or corrosion will have to be replaced.
Radar Installation• Line up all three screws with the through hole adjusters and hold the radar in place.
• Use a T-20 torx bit and ratchet and carefully install all three radar screws. Install so that about half of the threads are fully installed in the through hole adjusters.
• Plug in the electrical connector and make sure the rubber boot is fully covering the connector.
• Transition…..Once the radar has been initially installed, it will have to be properly aligned. The alignment process consists of two steps, vertical and horizontal. Let’s take a look at the vertical alignment process first.
HORIZONTAL SCREW
VERTICALSCREW
Radar Alignment Procedure
VERTICALSCREW
Connector Up Connector Down
Radar Vertical Alignment• Take a digital level and place it on the shop floor directly in front of the truck and underneath the radar. Make sure the suspension is at normal ride height.
• Zero the level.
• Use the T-20 torx bit; adjust the vertical alignment screw accordingly to achieve a reading of 90 degrees. Radar needs to be perpendicular to the floor.
• Transition……Once the vertical alignment has been set, the next step will be to road test the truck and perform the horizontal alignment.
Radar Horizontal Alignment• Have to drive the truck in order to perform.
• Start up the truck and press the mode button on the display twice to get to the radar alignment screen.
• Drive on a straight, flat road and track a vehicle.
• Screen will be blue when not tracking a vehicle; will turn green when tracking a vehicle and show distance.
• Start tracking a vehicle and monitor the bar graph on the display.
• Will start to settle in, but will not sit in one spot. Let lead vehicle increase distance to around 250 ft.
• Stop the truck and make the appropriate adjustment to the horizontal alignment screw with T-20 torx.
• Drive truck again after making the adjustment and track a vehicle again to verify proper alignment. Should be able to track 350 – 400 ft
• Return to the shop and re-install the fascia. Make sure the OnGuard logo is in the proper orientation.
39
Radar Horizontal Alignment
SLIDING BAR
Checking Radar Horizontal Alignment
Radar Alignment Screen
Parts.. Check Part Number on Tag
Explanation of Radar Data Example
•The Haptic Warning occurred with a lead vehicle decelerating at about 0.1 g (fairly typical of a car approaching a stop sign or red traffic light) and was slowed to 16 mph when the Haptic Warning activated. The vehicle with the radar was still travelling 54 mph, decelerating at only 0.02 g (maybe off-accelerator for a loaded truck, accelerator lifting but not at zero position for an empty or bobtail truck); the driver’s brake pedal was released. The lead vehicle was 190 feet away when the Haptic Warning became active, but if both vehicles continued at constant deceleration in a straight line, collision would have occurred within 3.2 seconds. The radar had been locked onto the lead vehicle for over 4 seconds, so there is high confidence in the accuracy of the target.
Literature: www.meritorwabco.com
• SP-0818 – OnGuard Driver Tips.
• TP-08122 – OnGuard Display Operating Instructions.
• MM-0951 – OnGuard Maintenance Manual.
• SP-0853 – OnGuard Information.
Driver Tips Video
