a. For full-time-powered ABS (usually obtaining power over the
blue line of the J560 connector): The trailer ABS indicator lamp
will function just like the tractor ABS indicator lamp, listed above.
b. For brake-light-only powered ABS: Each time the brakes are
applied, the indicator lamp will illuminate for approximately three
(3) seconds and then turn off. If the indicator lamp remains on
during braking, the trailer’s ABS may not be operating. The trailer
will retain normal service braking, although without the benefits
of ABS. Have the trailer serviced by a qualified technician as
soon as possible to restore ABS operation.
Bendix® Automatic Traction Control (ATC)/Electronic Stability Program (ESP®)
Indicator Lamp (Optional)
If your vehicle is also equipped with the optional ABS features, the Bendix® Automatic
Traction Control (ATC) or Bendix® Electronic Stability Program (ESP) system, a third
indicator lamp will be installed on the dash. (The same indicator lamp is also used
to indicate the ATC Mud/Snow mode.)
• During the bulb check at vehicle ignition your ATC/ESP indicator lamp will
illuminate for approximately two-and-a-half (2.5) seconds and then turn
off. If the ATC/ESP indicator lamp does not illuminate at ignition – or if it
remains on steadily (not flashing) after ignition, or if it illuminates steadily
(not flashing) while you are driving (except in off-road mode) – the ATC or
ESP system may not be fully functional or its operation may be completely
disabled. If this happens, your vehicle will still have normal service braking
and it still can be driven, although without the benefits of ATC or an ESP
system. Have the vehicle serviced by a qualified technician as soon as
possible to restore full ATC/ESP system functionality.

14

Understanding the Bendix® Antilock Braking System (ABS)
Indicator Lamps (Non-FMVSS-136-compliant Vehicles) (cont.)

At Vehicle Startup with
Vehicle not Moving

• T he Bendix® ATC/ESP system indicator lamp also flashes continually – at
different blink speeds – to show that:
a. The Mud/Snow mode is being used; or
b. During a Bendix ATC or ESP system intervention event.
• At speeds up to 25 mph (40.2 kph), if your vehicle is operating in
the – optional – Bendix® Antilock Braking System (ABS) system off-road
mode, the ATC/ESP indicator lamp will illuminate and remain on to remind
you that Bendix ESP system functions are disabled.

Mode

ABS Lamp

ATC/ ESP
Lamp

Trailer ABS
Lamp

Ignition on - startup
(trailer with PLC)

On for
three (3)
seconds*

On for 2.5
seconds*

On for three
(3) seconds*

Three (3) seconds
after ignition (with
no Diagnostic
Trouble Codes
[DTCs])

Lamp off*

Lamp off*

Lamp off*

Special Mode Operation

Normal
ABS
Off-road
Mode

Deep
Mud/
Snow
Mode

During
an ATC
event

Lamp
flashes
slowly
(approx.
every 2.5
seconds)

Normal

Off

During
an ATC/
ESP event

Off

Lamp on
(ESP is
disabled)

•
•
•
•

Lamp flashes
quickly

*If any of the described lamp behaviors
do not occur – or if the lamp remains
on during operation – have the vehicle
serviced by a qualified technician as
soon as possible to restore full system
functionality. Check with your OEM for
variations on indicator lamp timings
as compared with Bendix set indicator
lamp timings.

Uses dash switch
Not for firm road surfaces
Allows more wheel lock-up (less ABS intervention)
Mode only applies under 25 mph (40.2 kph). Over 25
mph, the system reverts to full ABS – including ESP,
and the ATC/ESP lamp turns off.

Lamp flashes
slowly
(approx.
• Uses dash switch
every 2.5
• Not for firm road surfaces
seconds)
• Increases allowable wheel slip during ATC
interventions
Lamp flashes
quickly

During an Automatic Traction
Control (ATC) event

Lamp flashes
• Reduces wheel slip during acceleration at low speeds
quickly

During an ESP event

Lamp flashes • System intervenes to reduce the risk of rollovers, loss of
quickly
control, etc.

Refer to the specific ABS Controller’s Service Data Sheet on B2Bendix.com.

15

Understanding the Bendix® Antilock
Braking System (ABS) Indicator Lamps
(FMVSS-136-compliant Vehicles)
ESC
ATC

Bendix® Antilock Braking System (ABS) Indicator Lamp
An amber ABS indicator lamp is typically located on the dashboard.
• At each vehicle ignition, your ABS indicator lamp should illuminate as
a bulb check for approximately three (3) seconds and then turn off.
If the lamp does not illuminate at ignition, you should have the
vehicle serviced by a qualified technician as soon as possible.
NOTE: Without a functioning indicator lamp, you may not be able to
determine the ABS status without using an external diagnostic tool.
• If the indicator lamp remains on for more than three (3) seconds after
ignition, or if it illuminates while you are driving, the ABS system may
not be fully functional or may be completely disabled. If the ABS is
completely disabled or not functioning properly, your vehicle will
still have normal service braking and it still can be driven, although
without the benefits of ABS. Have the vehicle serviced by a qualified
technician as soon as possible to restore full ABS functionality.
• The ABS indicator lamp is also used to indicate the optional off-road
ABS mode. The indicator lamp will flash continually when the vehicle is
operating in the off-road mode. [NOTE: When the ABS off-road mode
is engaged, stability functions are disabled at speeds below 11 mph
(17.7 kph). The Bendix Electronic Stability Control (ESC) Indicator lamp
will illuminate to indicate that the stability systems are disabled.] See
Page 4 of this manual for additional sources of information about the ABS
off-road operating mode.
Trailer ABS Indicator Lamp
The trailer ABS indicator lamp is dash-mounted.
• All trailers built since March 2001 are able to communicate with the
towing vehicle and operate the trailer ABS indicator lamp on the towing
vehicle’s dash. The trailer ABS indicator lamp functions just like the
tractor ABS indicator lamp. It is illuminated for approximately three
(3) seconds after each vehicle ignition, then extinguished – unless a
problem develops with the trailer ABS during operation.

16

Understanding the Bendix® Antilock Braking System (ABS)
Indicator Lamps (FMVSS-136-compliant Vehicles) (cont.)
• A
ll new trailers built since March 1, 2001 are equipped with an amber
Bendix® Antilock Braking System (ABS) indicator lamp located near the
rear of the trailer on the driver’s side. The operation of the indicator lamp
varies depending on how the ABS system is powered:
a. For full-time-powered ABS (usually obtaining power over the
blue line of the J560 connector): The trailer ABS warning lamp
will function just like the tractor ABS indicator lamp.
b. For brake-light-only powered ABS: Each time the brakes are
applied, the indicator lamp will come on for approximately
three (3) seconds and then turn off. If the lamp remains on
during braking, the trailer’s ABS may not be operating. The
trailer will retain normal service braking, although without
the benefits of ABS. Have the trailer serviced by a qualified
technician as soon as possible to restore ABS operation.
Bendix® Automatic Traction Control (ATC) Indicator Lamp (Optional)
If your vehicle is also equipped with the optional Bendix® Automatic Traction
Control (ATC) feature, a third indicator lamp may be installed on the dash. (The
same indicator lamp is also used to indicate the ATC Mud/Snow mode.)
• During the bulb check at vehicle ignition your ATC indicator lamp will
illuminate for approximately two-and-a-half (2.5) seconds and then
turn off. If the ATC indicator lamp does not illuminate at ignition – or
if it remains on steadily (not flashing) after ignition, or if it illuminates
steadily (not flashing) while you are driving (except in off-road
mode) – the Bendix ATC system may not be fully functional or its
operation may be completely disabled. If this happens, your vehicle
will still have normal service braking and it still can be driven, although
without the benefits of Bendix ATC system. Have the vehicle serviced
by a qualified technician as soon as possible to restore full Bendix
ATC system functionality.
• The ATC system indicator lamp also flashes continually – at different
blink speeds – to show that:
a. The Mud/Snow mode is being used; or
b. During a Bendix ATC or Electronic Stability Program (ESP®)
system intervention event.

17

Understanding the Bendix® Antilock Braking System (ABS)
Indicator Lamps (FMVSS-136-compliant Vehicles) (cont.)
Bendix® Electronic Stability Control (ESC) Indicator Lamp
A Bendix® Electronic Stability Control (ESC) indicator lamp is located on the dashboard.
• At each vehicle ignition, your ESC indicator lamp should illuminate as a bulb
check for approximately three (3) seconds and then turn off. If the lamp
does not illuminate at ignition, you should have the vehicle serviced by
a qualified technician as soon as possible. NOTE: Without a functioning
indicator lamp, you may not be able to determine the ESC status without
using an external diagnostic tool.
• If the indicator lamp remains on for more than three (3) seconds after
ignition, or if it illuminates while you are driving, the ESC system may not
be fully functional or may be completely disabled. If the ESC is completely
disabled or not functioning properly, your vehicle will still have normal
service braking and it still can be driven, although without the benefits
of ESC. Have the vehicle serviced by a qualified technician as soon as
possible to restore full ESC functionality.
• The ESC indicator lamp can blink during an ESC event.
• When the ABS off-road mode is activated, ESC will be disabled and the ESC
indicator lamp will be illuminated at vehicle speeds below 11 mph (17.7 kph).

18

Understanding the Bendix® Antilock Braking System (ABS)
Indicator Lamps (FMVSS-136-compliant Vehicles) (cont.)
ESC

At Vehicle Startup with
Vehicle not Moving

ATC

Mode

ABS
Lamp

ATC
Lamp

Trailer ABS
Lamp

ESC
Lamp

Ignition on - start
up (trailer with
PLC)

On for
three (3)
seconds*

On for 2.5
seconds*

On for
three (3)
seconds*

On for three
(3) seconds*

Three (3)
seconds after
ignition (with no Lamp off*
Diagnostic Trouble
Codes)

Lamp off*

Lamp off*

Lamp off*

Special Mode Operation

Normal
ABS Offroad
Mode

During
an ATC
event

Lamp
flashes
slowly
(approx.
every 2.5
seconds)

Lamp off

Lamp on
below
11 mph
(17.7 kph)

Lamp flashes
quickly

Lamp
off

Lamp
off

Bendix® Antilock Braking System (ABS)
Bendix® Automatic Traction Control (ATC)
Bendix® Electronic Stability Control (ESC)
Bendix® Electronic Stability Program (ESP®)

*If any of the described lamp
behaviors do not occur – or if
the lamp remains on during
operation – have the vehicle
serviced by a qualified
technician as soon as
possible to restore full system
functionality. Check with your
OEM for variations on dash
lamp timings as compared to
Bendix set lamp timings.
• Uses dash switch
• Not for firm road surfaces
• Allows more wheel lock-up
(less ABS intervention)
• Mode only applies under
11 mph (17.7 kph). Over
11 mph (17.7 kph), the
system reverts to full ABS including ESP - and the ESC
lamp turns off.

Normal

Lamp off

Lamp flashes
slowly
(approx.
every 2.5
seconds)

During
an ATC
event

Lamp off

Lamp flashes
quickly

Lamp
off

During an Automatic Traction
Control (ATC) Event

Lamp flashes
quickly

Lamp
off

• Reduces wheel slip during
acceleration at low speeds

During an ESP Event

Lamp off

Lamp
flashes
quickly

• System intervenes to reduce
the risk of rollovers, loss of
control, etc.

Deep
Mud/
Snow
Mode

• Uses dash switch
• Increases allowable
wheel slip during ATC
interventions
• Not for firm road surfaces

Refer to the specific ABS Controller’s Service Data Sheet on B2Bendix.com.

19

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