for automatic lift axle control (see below). A pressure
threshold switch must be installed in the lift bag for the
lift axle and connected to the ECU. The ECU can then
monitor the position of the lift axle and will compensate
correctly for the load transfer to the other axle(s) when
the lift axle is raised.
Mounting
Bolts

Rubber Link
and Rod

Load Sensor
FRONT OF TRAILER
Vertical Linkage Rod
Adjustable Linkage
with Rubber Link
Axle Attachment
Bracket

•

Lift Axle Control: The TABS‑6 ADV MC module can be
configured to automatically raise (and lower) lift axle(s)
when a pre-configured load is sensed.

•

Trailer ABS Indicator Lamp: Controlled by the ECU
to show the ABS status, the trailer ABS indicator lamp
illuminates when a DTC is active. See Figure 4. If there
are no ABS DTCs present, when ignition power is applied
to the ECU, the lamp will illuminate as a bulb check lasting
typically two (2) seconds, up to six (6) seconds at most. If
Low Pressure Warning Emergency (LPWE) is active, the
ABS indicator lamp will be on until the condition is clear.

Figure 4 – Trailer-Mounted ABS Indicator Lamp

•

WSS: Located at selected hubs, WSS detect the rotation
of individual wheels and send an electrical signal to the
ECU proportional to the rotational velocity. See Figures
5a and 5b.

•

Pigtail Wiring Harness: A power pigtail harness is
required. Auxiliary harnesses are available, as needed.
See Figure 6.

Use of cable ties/tie wraps to attach WSS leads to
rubber hoses/jounce lines is not approved. The hose
may expand during braking due to air pressure and the
cable tie may not, so the conductor material/insulation
of the WSS extensions may be damaged. Bendix instead
recommends only open-ended clips be used to hold
sensor leads to jounce lines.
90° Angle WS-24 Sensor
(with trade dress)

Straight WS-24 Sensor
(with trade dress)

90° Angle WS-24 Sensor

Straight WS-24 Sensor

Axle Strap-Style
Fastener Clamp

Figure 3 – Typical External Load Sensor Installation
For more information, refer to S-1588, Spring Deflection Sensor, on B2Bendix.com.

NOTE: The appearance of the
WS-24 wheel speed sensors may
vary depending upon the date and
location of manufacture, but they are
interchangeable provided they are the
same type (e.g., straight or 90°).

6

Figure 5a – Bendix ® WS-24™ Wheel Speed Sensors

Part No. K134931
NOTE: Stainless steel clamping sleeves require that a high-temperature-rated silicon- or lithiumbased grease be applied to the sensor body. This lubrication will keep the movement between the
sensor and the clamping sleeve independent from one another.
Swoosh
Symbol

KnorrBremse Logo

Figure 5b – Steel Clamping Sleeve
1

4
3

2
(FACE VIEW)

P1
DIAGNOSTIC CABLE

(HARNESS - K143203)

1

12

6

7

J1

1

4

2

3

(FACE VIEW)

P1

DIAGNOSTIC CABLE

(FACE VIEW)

6

1

4

3

P2

P2 AUXILIARY CABLE

(HARNESS - K143204)

(FACE VIEW)

1

4

2

3

1

12

6

7

(FACE VIEW)

P1
DIAGNOSTIC CABLE

(FACE VIEW)

(Harness - K143207)

1

12

6

7

(FACE VIEW)

4

2

1

3

P4

P4 AUXILIARY CABLE

(FACE VIEW)

5-PIN POWER AND
INDICATOR LAMP (POWER/
INDICATOR LAMP)

7-PIN ECU CONNECTOR

(POWER HARNESS - K022146)

SENSOR CABLE
COVER END OF
JACKET DUAL
HEAT SHRINK

SPEED SENSOR ADAPTER
(DIFFERENT LENGTHS AVAILABLE)

O-RING
(LUBRICATED)

WHEEL SPEED SENSOR
(DIFFERENT LENGTHS AVAILABLE)

Figure 6 – Examples of Pigtail Wire Harnesses
7

5. MOUNTING
Circuit

Frame (Chassis) Mount
The TABS‑6 ADV MC module provides three (3) M10,
1.18-in. (30 mm) studs for frame-mounting directly to a trailer
cross-member. The TABS‑6 ADV MC module uses three (3)
Class-8 steel M10x1.5 lock nuts with washers, torqued to 354
± 44.4 in.-lbs (40 ± 5 N•m). A bracket may be used if direct
mounting to a cross-member is not possible.

6. PIGTAIL WIRING HARNESSES

See Figure 6. Several pigtail wire harnesses are available
to connect the TABS‑6 ADV MC module with other trailer
system components. Pigtail harnesses are weather-sealed
at the connector interface and are clearly labeled for proper
installation. Because of the over-molded design of the wiring
harnesses, Bendix recommends that if damage or corrosion
occurs, the complete harness be replaced.
WSS Connectors
The TABS‑6 ADV MC module includes two (2) primary and
two (2) secondary WSS connections separate from the main
vehicle pigtail harnesses, and each requires a separate
harness. The connector of each WSS is a 2-pin Deutsch
DT series.
ECU Connectors
The TABS‑6 ADV MC module ECU has four (4) connectors
(in addition to the WSS connectors mentioned above).
The primary connector is a 7-pin custom series screwon-type connector used to connect to the vehicle’s
power pigtail harness. The main connector is a 12‑pin
Deutsch-DT-series-style connector, used for auxiliary
I/Os. Finally, the auxiliary connectors 2.3 and 2.4 are 6-pin
Deutsch-DT-series-style connectors, used for additional
auxiliary I/Os.
Power and Ground
Trailer electrical power is supplied to the TABS‑6 ADV MC
module from the ignition and brake light circuits.
See Tables 1 and 2 for output values and pin locations.
Function Mode

Value

Operating Range

8.0 to 32.0 VDC

ECU Active

150 mA @ 12 VDC

ABS Active

2.0 A @ 12 VDC

Table 1 – Values for Outputs

8

7-Pin
Trailer
Conn.

5-Pin
ABS
Conn.

7-Pin
ECU
Conn.

7

B

1

4

A

2

1

E

4

N/A

D

5

N/A

N/A

6

N/A

N/A

7

Ignition Power PLC
(Blue Wire)

Brake Light Power
(Red Wire)

Ground

(White Wire)

Indicator Lamp

(White/Green Wire)

TT-CAN Hi*

(White/Green Wire)

TT-CAN Lo*

(White/Brown Wire)

*Tractor Trailer CAN is only available for ECUs labeled with a component index
of M002 and higher.

Table 2 – Main Power Harness and Connectors Pin Out

Power/ABS Indicator Lamp Connector
The TABS‑6 ADV MC module pigtail uses a TTMA RP
97‑99 5-pin Packard Weather Pack connector for brake light
power, constant power, ground, and the trailer-mounted ABS
indicator lamp.
SAE J1939 (CAN) Connector
See Figure 6.
The TABS‑6 ADV MC module 12-pin auxiliary harnesses
typically include a 4-pin connector used for various ECU
communications. Typical uses include J1939 diagnostics
and connection to the Bendix TIM.
Auxiliary I/O Connector
The TABS‑6 ADV MC module provides an option for up to six
(6) auxiliary I/Os. For a pin-out, see Section 11.
Examples of uses of the auxiliary connectors are:
• Lift axle sensing
• Rear axle suspension air bag dump
• SAE J1939 diagnostics
• Automatic lift axle control
• External spring deflection sensor for mechanical spring
suspension

7. ABS INDICATOR LAMP
Trailer-Mounted Lamp
The TABS‑6 ADV MC module controls an ABS indicator lamp
to show the trailer ABS status. With power supplied by the
towing vehicle – if there is an active DTC, or during the bulb
test at startup – the module illuminates the ABS indicator
lamp by providing a 12.0 VDC signal. (The other side of the
lamp is grounded.) The ABS indicator lamp output uses pin
5 of the 7-pin connector on the module.
Dash-Mounted Lamp (PLC-Controlled)
The TABS‑6 ADV MC modules use SAE J2497 standards to
support Power Line Carrier (PLC) communication. The status
of the trailer ABS is transmitted over the ignition power wire
(the blue wire of the J560 connector) – pin 1 of the 7-pin
module connector.
If there is an active DTC during the bulb check at startup,
the TABS‑6 ADV MC module will transmit a signal over the
power line to the towing vehicle’s ECU. The towing vehicle’s
ABS controller will then illuminate the trailer ABS indicator
lamp mounted on the dash.

8. B E N D I X ® W S - 2 4 ™ W H E E L S P E E D
SENSORS (WSS)
Wheel speed data is provided to the TABS‑6 ADV MC module
by the Bendix® WS-24™ Wheel Speed Sensors (WSS).
Typically, the WS-24 WSS is installed in a mounting block that
is welded to the axle housing. The WS-24 WSS are protected
by a stainless steel sheath and are designed to be used with
stainless steel clamping sleeves (sometimes referred to as
a “retainer bushing”, “friction sleeve”, or “clip”) (See Figure
5). The clamping sleeve provides a friction fit between the
mounting block bore and the WS-24 WSS.
Vehicles have an exciter ring (or “tone ring”) as part of the
wheel assembly. (The default setting expects a 100-tooth
tone ring to be used. See Troubleshooting: Section E for more
information.) As the wheel turns, the teeth of the exciter ring
pass the WSS, generating an AC signal which is delivered
to the TABS‑6 ADV MC module ECU. The signal varies in
voltage and frequency as the wheel speed changes.
Vehicle axle and ABS control configurations determine if two
(2) or four (4) WSS are required. See Figures 19 and 20 for
an electrical system schematic showing WSS connector pin
locations.

1. For

increased corrosion protection, Bendix recommends
that a high-temperature-rated silicone- or lithium-based
grease be applied to the interior of the mounting block,
the sensor, and to a new clamping sleeve.
2. Install the new clamping sleeve fully into the block, with
the retaining tabs toward the inside of the vehicle. Please
note that Bendix WS-24 WSS must use the correct
clamping sleeve to avoid problems associated with
reduced retention force, such as sensor movement and
resulting in ABS DTCs. See Figure 5.
3. G
ently push (DO NOT STRIKE) the sensor into the
mounting block hole until it bottoms out on the face of the
tone ring. Secure the cable lead wire to the knuckle/ axle
housing 3-6 in. (7.62-15.24 cm) from the WSS.
4. A
pply a small amount of dielectric non-conductive grease
to both the WSS and the harness connectors.
5. E
ngage the connectors and push them together until the
lock tab snaps into place. It is permissible to use an extra
wire retainer (Bendix part number 300122, or equivalent),
if available, to hold the connectors together.
The friction fit allows the WS-24 WSS to slide back and
forth under force, but to retain its position when the force is
removed. When the WS-24 WSS is inserted all the way into
the mounting block and the wheel is installed on the axle,
the hub exciter contacts the sensor, which pushes the WSS
back. Also, normal bearing play will “bump” the WSS away
from the exciter. The combination of these two (2) actions
will establish a running clearance, or air gap, between the
WSS and the exciter.

Correct WSS installation is necessary for optimal ABS
operation.

Wheel bearing maintenance is an important part of
keeping the WSS in the correct position. Excessive
wheel end play can result in DTCs in cases where the
WSS is pushed too far away from the tone ring for a good
signal to be produced. Maintain wheel bearings per the
manufacturer's recommendations.

NOTE: If the trailer is equipped with a lift axle that will use
WSS, it is important that secondary sensors SE and SF be
used for this axle. See the system diagrams included in this
document. In all cases, the primary WSS must be located
on the fixed axle. For 2S/2M systems, the fixed axle sensors
are SC and SD.

9

9. SAE J2497 (PLC) DIAGNOSTIC LINK
All newer towed vehicles transmit a signal over the power line
to the towing vehicle ABS ECU. The signal, using a heavy
vehicle industry standard known as Power Line Carrier (PLC/
J2497), is broadcast by the trailer ABS ECU over the blue wire
(ignition power line) of the SAE J560 connector and controls
an in‑cab trailer ABS indicator lamp. See Figures 7 and 8.

An oscilloscope can also be used to verify the presence and
strength of a PLC signal on the power line. The PLC signal is
an amplitude- and frequency-modulated signal. Depending
on the load on the power line, the amplitude of the PLC signal
can range from 2.5 mV p‑p to 7.0 V p‑p.
Suggested oscilloscope settings are: AC coupling, 1 V/div,
100 µsec/div. The signal should be measured on pin 7 of the
J560 connector at the nose of the trailer.

10. SAE J1939 (CAN) DIAGNOSTIC LINK
The TABS‑6 ADV MC module provides a data link for
transmitting CAN information following the SAE J1939
standard.
ACom Diagnostic Software and the Bendix Trailer Information
Module both support CAN communication with the TABS‑6
ADV MC module.
Figure 7 – Power Line Without PLC Signal

Ignition power must be provided to the TABS‑6 ADV MC
module for the diagnostic link to be active.

11. AUXILIARY I/O
The TABS‑6 ADV MC module provides for up to six (6)
auxiliary I/O functions. Refer to Table 3.
ACom Diagnostic Software supports the configuration of the
TABS‑6 ADV MC module auxiliary I/Os.
Name

Figure 8 – Power Line With PLC Signal

Aux I/O 1

The TABS‑6 ADV MC module provides a data link for PLC
communication following the SAE J2497 standard.

(AuxIO1)

Bendix ACom Diagnostic Software and the Bendix TRDU
both support PLC communication with the TABS‑6 ADV MC
module.

(AuxIO2)

®

®

PLC communication is applicable for 12-V vehicle applications
only. The PLC communication is disabled for voltages greater
than 18 V.
Identifying and Measuring the PLC Signal
The TABS‑6 ADV MC module will continuously broadcast
PLC messages that indicate trailer ABS status. At power-up,
or during a trailer DTC condition, the TABS‑6 ADV MC module
will signal the tractor ABS unit to illuminate the dash-mounted