Bendix Commercial Vehicle Systems EC-80 ABS ATC SD - Manual (Page 13)

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FIGURE 8 - EXAMPLE OF BLINK CODE MESSAGE
Troubleshooting: Blink Codes and Diagnostic Modes
BLINK CODES
Blink codes allow a technician to troubleshoot ABS
problems without using a hand‑held or PC‑based diagnostic
tool. Instead, information about the ABS system is
communicated by the ECU using the ABS indicator lamp
to display sequences of blinks.
Note: The ECU will not enter the diagnostic blink code
mode if the wheel speed sensors show that the vehicle is in
motion. If the ECU is in the diagnostic blink code mode and
then detects vehicle motion, it will exit the blink code mode.
In addition, by operating the blink code switch as described
below, one of several diagnostic modes can be entered.
See Diagnostic Modes below.
Blink Code Switch Activation
When activating the blink code switch:
1. Wait at least two seconds after “ignition on.” (Except when
entering Reconfiguration Mode - see Reconfiguration
section on page 11)
2. For the ECU to recognize that the switch is activated
“on,” the technician must press for at least 0.1 seconds,
but less than 5 seconds. (If the switch is held for more
than 5 seconds, the ECU will register a malfunctioning
switch.)
3. Pauses between pressing the switch when a sequence
is required, (e.g. when changing mode) must not be
longer than 2 seconds.
4. After a pause of 3.5 seconds, the ECU will begin
responding with output information blinks. See Figure
10 for an example.
ECU DIAGNOSTICS
The Bendix ® EC‑80 ™ controller contains self‑testing
diagnostic circuitry that continuously checks for the normal
operation of internal components and circuitry, as well as
external ABS components and wiring.
Active Diagnostic Trouble Codes
When an erroneous system condition is detected, the
Bendix EC‑80 controller:
1. Illuminates the appropriate indicator lamp(s) and
disengages part or all of the ABS and ATC functions.
(See pages 8-9.)
2. Places the appropriate trouble code information in the
ECU memory.
3. Communicates the appropriate trouble code information
over the serial communications diagnostic link as
required. Hand‑held or PC‑based diagnostic tools
attach to the vehicle diagnostic connector, typically
located on or under the dash (See Figure 7).
FIGURE 7 - TYPICAL VEHICLE DIAGNOSTIC CONNECTOR
LOCATION (J1939)