•
•
•

•

Any time the steering angle sensor is removed
or replaced;
If the SAS wiring harness is repaired or replaced;
Any maintenance or repair work on the steering
linkage, steering column, steering gear, or other
related mechanism; or
Adjustment of the wheel alignment or wheel track.

If the SAS is not calibrated correctly, ESP functions
may not operate properly, which can result in loss of
vehicle control, potential collisions, property damage,
serious injuries, and/or death.

DIAGNOSTICS
Bendix SASs can only report diagnostic information,
including Diagnostic Trouble Codes (DTCs), when
connected to a Bendix brake control system ECU.
Stand-alone diagnostics are not possible.
DTCs can be read using Bendix ACom Diagnostic
Software. Depending on the vehicle OEM and brake control
ECU family, it may also be possible to read SAS DTCs
using the OEM service tool. Contact the vehicle OEM for
more information.

SAS WIRING INFORMATION
If it is necessary to troubleshoot, repair, or replace any
part of the wiring harness that connects to the Bendix
SAS-60, SAS-70, or SAS-80 to the brake control ECU,
contact the vehicle OEM for the appropriate troubleshooting
procedure, harnessing, and repair procedures.
NOTE: If the harness is replaced, calibrate the SAS once
the new harness has been installed.

All wires must be carefully routed to avoid contact
with rotating elements. Only use OEM components
to repair or replace the SAS harness. Install any
replacement parts according to the vehicle OEM's
published maintenance procedures.

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SAS TROUBLESHOOTING
To troubleshoot an SAS and the SAS vehicle harness,
complete the following steps:
1. Make the vehicle safe for maintenance by following
the General Safety Guidelines on page 2.
2. Turn the vehicle off and remove the key from the
ignition.
3. Remove the steering column shroud/sheathing.
Refer to the vehicle OEM's maintenance
instructions for the specific procedure required
to remove the steering column shroud and trim.
4. Unplug the SAS from the wiring harness.

8. With the harness disconnected and the multimeter
still in place on the power pins of the vehicle
harness, turn the ignition power from off to on.
Depending on the brake controller family, the
voltage may only be present momentarily, as some
brake controllers turn off power when it does not
receive a response from the unplugged SAS.
9. When the ignition is turned on, the multimeter
should read roughly 12V or 24V depending on the
SAS variant installed on the vehicle. Refer to Table 2
and refer to the OEM wiring diagram to confirm
appropriate supply voltage.

5. Using a multimeter, measure the resistance
between pins 3 and 4 at the electrical connector of
the SAS. This resistance should read 120 + 5 ohms.
If the resistance is outside of this range, replace
the SAS.
6. With the harness still disconnected from the SAS,
measure resistance between the power (pin 2)
and ground (pin 1) pins on the vehicle harness
with a multimeter. If resistance measures 0 ohms,
inspect for a short in the harness per the vehicle
OEM troubleshooting procedure to diagnose and
repair the short.
7. With the harness still disconnected from the SAS
and the vehicle ignition off, measure the voltage
between the power (pin 2) and ground (pin 1) pins
on the vehicle harness with a multimeter. There
should be no voltage present if the key is off. If
voltage is detected, refer to the OEM procedure
for troubleshooting a short to battery in the wiring
harness.
NOTE: For Bendix EC-80 or EC-60 ECUs, confirm
that voltage is not present on pins 11 and 10 on
the X4 connector in the same scenario. If voltage
is present on those pins with the key off, refer to
the appropriate Service Data sheet for additional
troubleshooting information. Refer to SD-13-4986,
EC-80 ESP Service Data Sheet, or SD-13-4869,
EC-60 ESP Service Data Sheet, on B2Bendix.com.
PIN 1 PIN 2 PIN 3

PIN 4

PIN 5 PIN 6 PIN 7

PIN NO.

USE

1

Ground

2

Power

3

CAN High

4

CAN Low

5

Not Used

6

Not Used

7

Not Used

Table 1 – SAS Pinout

Figure 3 – Bendix SAS-60, SAS-70, and SAS-80 Wiring Pinout
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SAS Variant

12V

24V

SAS-60

Y

N

SAS-70

Y

N

SAS-80

Y

Y

Table 2 – SAS Variant Voltage

Always use the correct SAS sensor for the system
voltage of the vehicle. Failure to use the correct SAS
for the system could result in serious vehicle braking
and performance issues, including unnecessary ESP
system interventions and/or system faults leading
to loss of ESP functionality. These types of failures
can lead to a loss of control of the vehicle, potential
collisions, proper ty damage, serious injuries,
and/or death.
10. Check continuity of the power wires between the
SAS and the corresponding ECU it is connected
to. For vehicles equipped with EC-60 or EC-80,
refer to Table 3. For vehicles equipped with GSBC,
refer to Table 4.
Connector

Pin

SAS
EC-60/EC-80 ECU
ONLY

X4

Function

2

Power

1

Ground

11

Power

10

Ground

Table 3 – EC-60/EC-80 to SAS Electrical Pin Match
Connector

Pin

SAS

GSBC Central ECU
ONLY

N/A

Function

2

Power

1

Ground

Depending on the vehicle OEM, the GSBC
Central ECU to SAS electrical pin match
may vary. Refer to the vehicle OEM wiring
diagram for more information.

Table 4 – GSBC Central ECU to SAS Electrical Pin Match

SAS TROUBLESHOOTING (CONT.)
11. Check the continuity of the CAN Communication
wires running between the SAS and the
corresponding ECU it is connected to. For EC-60
and EC-80, refer to Table 5. For vehicles equipped
with GSBC, refer to vehicle OEM wiring diagram.
SAS Wire
Harness Terminal

EC-60/EC-80 ECU Wire
Harness Terminal

Measurement

4

X4-7

Verify Continuity

3

X4-8

Verify Continuity

Table 5 – EC-60/EC-80 Continuity Check Information

12. Make sure the ignition key is off. Reconnect the
SAS to the electrical wiring harness.
13. For EC-60 and EC-80 ECUs only, complete the
following:
a. Measure the resistance at the brake
control ECU harness connector between
pins 7 and 8 on connector X4.
•

If both the SAS and the YAS are plugged
in, the resistance between pins 7 and 8
should be 60 + 5 ohms.

•

If either the SAS or YAS are unplugged
or faulty, the resistance will read 120 +
5 ohms.

•

If both devices are unplugged, or the
harness is broken, the resistance will read
as "open" or very high resistance.

•

If the resistance is very low, the harness
is shorted.

•

If this test indicates a problem with the
harness, refer to the OEM procedure
for troubleshooting and repairing the
electrical harness.

b. Measure the continuity between pin 7 at the
brake control ECU harness connector, and
pin 4 on the SAS harness connector.
•

c.

If these pins are not continuous, troubleshoot,
repair, and replace the harness according
to the vehicle OEM procedure.

Measure the continuity between pins 8 at the
brake control ECU harness connector, and
pin 3 on the SAS harness connector.
•

If these pins are not continuous, troubleshoot,
repair, and replace the harness according
to the vehicle OEM procedure.

15. For GSBC ECUs only, refer to the OEM wiring
schematic to determine which ECU and pins the
SAS is connected to. To confirm that the harness
is intact and working properly, measure end to end
continuity between the SAS harness connector
and the connected vehicle ECU. If issues with the
harness are discovered, follow the vehicle OEM
troubleshooting procedure.
16. After troubleshooting is complete and the issue in
the SAS or harness has been resolved, reinstall
the SAS (per Installation instructions starting on
page 4), wiring harness, and any other components
that were removed.
17. Calibrate the SAS using ACom Diagnostic
Software or the appropriate vehicle OEM service
tool. Refer to the SAS Calibration section on
page 5 for more information.

WARRANTY INFORMATION
For warranty information, refer to BW8003, Limited
Warranty - Electronic Systems, on B2Bendix.com.

BENDIX TECHNICAL SUPPORT
The Bendix Tech Team is available via email at
techteam@bendix.com and by phone at 1-800-AIR-BRAKE
(1-800-247-2725), option 2, Monday through Thursday,
8:00 a.m. to 6:00 p.m. and Friday, 8:00 a.m. to 5:00 p.m.
ET. Follow the instructions in the recorded message.

Unless otherwise indicated, the trademarks used in this document, including Bendix, are United States trademarks
owned by, or licensed to, Bendix Commercial Vehicle Systems LLC.
SD-27-4709 Rev 001 © 3/2026 Bendix Commercial Vehicle Systems LLC, a member of Knorr-Bremse • All Rights Reserved

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