Diagnostic Blink Code Switch
A momentary switch that grounds the ABS Indicator Lamp output is used to place the ECU into the diagnostic blink code mode and is typically located on the vehicle’s dash panel.
ABS Off-Road Switch and Indicator Lamp Operation
WARNING: The ABS off-road mode should not be used on normal, paved road surfaces because vehicle stability and steerability may be affected. When the ECU is placed in the ABS off-road mode, the ABS Indicator Lamp will flash constantly to notify the vehicle operator that the off-road mode is active.
Premium EC-60™controllers use a dash-mounted switch to place the ECU into the ABS off-road mode. In some cases, ECUs may also be put into the ABS off-road mode by one of the other vehicle control modules, using a J1939 message to the EC-60™controller.
(If you need to know if your EC-60™controller uses a J1939 message to operate the lamp, e-mail ABS@bendix.com, specifying the ECU part number, or call 1-800-AIR-BRAKE and speak to the Bendix TechTeam.)
Stop Lamp Switch (SLS)
The Premium EC-60™controller monitors the vehicle stop lamp status. Certain vehicle functions, such as ATC and All-Wheel Drive (AWD), use the status of the stop lamp to know the driver’s intention. This can be provided to the ECU via J1939 communications, or hardware input.
EC-60™CONTROLLER OUTPUTS
Bendix® M-32™and M-32QR™Pressure Modulator Valves (PMV)
The Bendix® M-32™and M-32QR™pressure modulator valves (PMV) are operated by the EC-60™controller to modify driver applied air pressure to the service brakes during ABS or ATC activation (See pages 6-8). The PMV is an electro- pneumatic control valve and is the last valve that air passes through on its way to the brake chamber. The modulator hold and release solenoids are activated to precisely modify the brake pressure during an antilock braking event. The hold solenoid is normally open and the release solenoid is normally closed.
Traction Control Valve (TCV)
Premium EC-60™controllers will activate the TCV during differential braking ATC events. The TCV may be a separate valve or integrated into the rear axle relay valve.
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ABS Indicator Lamp Control with Optional Diagnostic Blink Code Switch (Cab and Frame ECUs)
Cab and frame-mount EC-60™controllers have internal circuitry to control the ABS Indicator Lamp on the dash panel.
The ABS Lamp Illuminates:
1.During power up (e.g. when the vehicle is started) and turns off after the self test is completed, providing no Diagnostic Trouble Codes (DTCs) are present on the tractor.
2.If the ECU is unplugged or has no power.
3.When the ECU is placed into the ABS off-road mode (the lamp flashes rapidly).
4.To display blink codes for diagnostic purposes after the external diagnostic switch is activated.
Certain models of the EC-60™controller communicate with other vehicle control modules to operate the ABS Indicator Lamp using serial communications. (If you need to know if your EC-60™controller uses serial communications to operate the lamp, e-mail ABS@bendix.com, specifying the ECU part number, or call 1-800-AIR-BRAKE and speak to the Bendix TechTeam.)
Indicator Lamp Control Using Serial Communications Links
As mentioned above, depending on the vehicle manufacturer, the dash indicator lamps (ABS, ATC, and trailer ABS) may be controlled using serial communications links. In these cases, the EC-60™controller will send a serial communications message over the J1939 or J1587 links indicating the required status of the lamp(s). Another vehicle control module receives the message and controls the indicator lamp(s).
Retarder Relay Disable Output
The retarder relay disable output may be used to control a retarder disable relay.
When configured to use this output, the ECU will energize the retarder disable relay and inhibit the use of the retarder as needed.
SAE J1939 Serial Communications
A Controller Area Network (CAN) data link (SAE J1939) is provided for communication. This link is used for various functions, such as:
•To disable retarding devices during ABS operation
•To request torque converter lock-up during ABS operation
•To share information such as wheel speed and ECU status with other vehicle control modules
Premium EC-60™controllers utilize the J1939 data link for ATC and drag torque control functions.
