Bendix Commercial Vehicle Systems MC-11 TRACTOR ANTILOCK 4/04 - Manual (Page 9)

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6. Install o-ring(5) into its groove in the piston(6). Install
piston(6) into the M-12 ™ modulator body. The piston stem
fits into the small hole in the center of the body.
7. Install o-ring(4) onto the protrusion on the bottom of the
M-12 ™ modulator solenoid assembly(2). Install the
solenoid assembly onto the valve body(3). The solenoid
assembly will fit on the M-12
™ modulator body in any of
four orientations, 90 degrees apart. Secure the solenoid
assembly to the valve body with the four 1/2" bolts. Torque
the bolts to 120-150 in. lbs.
8. Install gasket(7) onto the EC-11 ™ controller. Install the
EC-11 ™ controller(1), as shown in Figure 9, by plugging
the 4-pin electrical connector from the solenoid assembly
into the socket in the bottom of the controller. Press in
until lock tab engages. Ensure engagement by pulling
the connector lightly. Place the controller on to the
solenoid assembly and secure with the four 1/2" bolts
and lockwashers. Torque to 30-60 in. lbs.
DIAGNOSING AND LOCATING A SYSTEM
PROBLEM
GENERAL
The EC-11 ™ controller contains self-test and diagnostic
circuitry that continuously checks for proper operation of
the entire antilock system, including wiring continuity. A dash
light, controlled by the EC-11
™ controller, advises the driver
of the antilock system condition. Specific component
condition is provided by a series of Light Emitting Diodes
(LEDs) displayed through a “window” in the EC-11
™ controller
housing.
The dash light’s separation from the EC-11 ™ controller
diagnostic window allows the driver to be aware of any
problems that occur but not to be confused by diagnostic
information.
A special feature of the MC-11 ™ antilock system is failure
latching. When the controller senses an error, it stores the
condition in memory, disables antilock, and illuminates the
dash light and the appropriate LEDs on the EC-11
™ controller.
The condition is truly stored–it is not cleared by loss of
power to the EC-11
™ controller. The LEDs will re-light when
power is restored and will remain illuminated until the problem
is corrected. After the actual problem is discovered and
corrected, maintenance personnel can clear the EC-11
™
controller diagnostics by passing a small magnet over the
RESET area in the “window.”
DIAGNOSTIC LEDs
There are six LEDs and a magnetic reset switch on the
EC-11
™ controller diagnostic window.
“VOLT” LED
This red LED illuminates when power to the EC-11 ™ controller
falls outside the acceptable range of 9-18 volts. If the voltage
returns to within the acceptable range, the VOLT LED will
go off. This is the only LED that will reset itself when the
failure condition no longer exists.
“MOD” LED
This red LED illuminates AND LATCHES ON when solenoid
resistance is not within the acceptable range of 9.5-11.5
ohms. It can also illuminate if excessive electrical spikes
are present in the power line.
“SNS 1” AND “SNS 2”
The red SNS LEDs illuminate AND LATCH ON to indicate
any one of a number of permanent or intermittent failures.
(For example, open or shorted wheel speed sensor, open or
shorted sensor wiring, no wheel speed signal.)
“CONT” LED
This red LED illuminates AND LATCHES ON if the EC-11 ™
controller is malfunctioning, or if excessive electrical spikes
are present in the power line.
“PWR” LED
This green LED illuminates and remains on during vehicle
operation to indicate that vehicle power is reaching the
EC-11
™ controller.
TROUBLESHOOTING
GENERAL
While the EC-11 ™ controller diagnostic display locates a
specific problem area, it is still necessary to determine
whether the problem resides in the component itself or the
wiring. Basically, the troubleshooting procedure that follows
is devoted to narrowing down the problem to either the wiring
or a specific antilock component.
RESET
VOLT
MOD
SNS1
SNS2
CONT
PWR