5
ABS INDICATOR LAMP
Trailer Mounted Lamp
The MC-30
™
controller controls an ABS indicator lamp
to indicate the trailer ABS status. The MC-30
™
controller
directly controls the ABS indicator lamp by providing a
12.0 VDC signal to turn it on. The other side of the lamp
is grounded. The MC-30
™
controller must be powered in
order to operate the trailer indicator lamp. Pin D3 of the
30-pin connector is the ABS indicator lamp output.
Dash Mounted Lamp (PLC Controlled)
MC-30
™
controller models with PLC will transmit a signal to
control a trailer ABS indicator lamp mounted on the dash
of the tractor. MC-30
™
controller will transmit the status of
the trailer ABS unit over the ignition power pin E1 of the
30-pin connector. The ignition power wire (blue wire of the
J560 connector) will carry this signal to the towing vehicle.
MC-30
™
controller models with PLC support communication
in accordance with SAE J2497.
WHEEL SPEED SENSORS
Wheel speed data is provided to the MC-30
™
controller
from the Bendix wheel speed sensors. See Figure 8 for
examples. Working with a tone (exciter) ring, the wheel
speed sensors provide the MC-30
™
controller with an AC
signal, which varies in voltage and frequency in relation
to the speed of the wheel. The MC-30
™
controller is
confi gured to receive wheel speed information from 100
tooth tone rings by default. Vehicle axle and ABS control
confi gurations determine if two or four wheel speed sensors
must be used. See the MC-30
™
controller’s electrical
system schematic
for wheel speed sensor connector pin
locations, Figure 16.
Circuit
7-Pin Trailer
5-Pin ABS
30-Pin ECU
Electrical
Power
Connector
Connector
Connector
Ignition Power (PLC)
Pin 7
B
Pin E1
(Blue
Wire)
Brake Light Power
Pin 4
A
Pin E3
(Red
Wire)
Ground
Pin 1
E
Pin D2
(White
Wire)
Indicator Lamp
N/A
D
Pin
D3
(White/Green
Wire)
Function Mode
Value
Operating Range
8.0 to 16.0 VDC
ECU Active
383
mA
ABS Active
2.4 A @ 12 VDC
(1 modulator)
ABS Active
4.5 A @ 12 VDC
(2 modulators)
CHART 2 - POWER AND GROUND
FIGURE 8 - BENDIX WHEEL SPEED SENSORS
CLIP AND SENSOR INSERTION
90° Speed
Sensors
Straight Speed
Sensors
PREVIOUS AND NEW CLAMPING SLEEVES
WS-24
sensors use
clamping
sleeves with
“BX” in a
swoosh
symbol
Previous
clamping
sleeves have
“BW” in a
diamond
Previous Bendix Wheel Speed Sensors
Previous sensors are all replaced by the
Bendix WS-24
™
wheel speed sensor shown below.
FIGURE 9
FIGURE 10
Wheel Speed Sensor Clips
The sensor spring clip is designed to fi rmly hold the wheel
speed sensor in place while also allowing the sensor to
adjust in position as the wheel and hub rotate. Wheel
bearing play and heavily loaded axles will cause sensors
to self-adjust. Proper sensor installation begins by fully
inserting the spring clip into the block, with the retaining
tabs toward the inside of the vehicle. See Figure 9.
