8-80
Published 01-14-2021 Control # 707-01
CARRIER
TMS9000-2 SERVICE MANUAL
Electrical Tests: Modulator Valves
NOTE:
Before testing the solenoid assembly of a suspect
modulator, its location on the vehicle should be
confirmed using the Troubleshooting or Start Up
procedure for the specific anti-lock controller in
use. (See the Service Data Sheet for the anti-lock
controller for this procedure at the Bendix website:
Proceed to the modulator in question and inspect its wiring
connector. Disconnect the connector and test the resistance
between the pins on the modulator. Refer to (Figure 8-82);
•
Hold to Source (41-42): Read 4.9 to 5.5 ohms.
•
Exhaust to Source (43-41): Read 4.9 to 5.5 ohms.
•
Exhaust to Hold (43-42): Read 9.8 to 11.0 ohms.
Individually test the resistance of each pin to vehicle ground
and note there is no continuity. If the resistance readings are
as shown, the wire harness leading to the modulator may
require repair or replacement. Before attempting repair or
replacement of the wire harness, refer to the test procedures
specified for the anti-lock controller in use for possible further
testing that may be required to substantiate the wire harness
problem. If the resistance values are not as stated, replace
the modulator.
ABS Sensor Adjustment
1.
Slide the notched end of an ABS sensor adjustment tool
(Figure 8-83) through the opening in the brake spider
until it rests against the sensor (the tool will go in the
hole at a slight angle).
NOTE:
It is not necessary to remove the wheel or drum to
adjust sensors using the adjustment tool.
2.
Press the sensor toward the wheel hub until the sensor
contacts the tooth wheel.
3.
Remove the sensor adjustment tool.
4.
Verify proper sensor adjustment by driving the vehicle.
This allows the ABS to perform an additional self test.
Once the vehicle reaches approximately 11 km/h
(7 mph), the ABS warning lamp will go out if the sensor
is properly adjusted.
5.
To check wheel speed sensor resistance, refer to
Troubleshooting Diagnostic Trouble Codes: Wheel
Speed Sensors.
Component Removal and Installation
Prior to returning the vehicle to service, make certain all
components and systems are restored to their proper
operating condition.
FIGURE 8-83
CAUTION
Possible equipment damage!
DO NOT use a screwdriver or sharp instrument to adjust
the sensor. Use of a sharp instrument could permanently
damage the sensor.
DO NOT use a hammer to drive the sensor into position.
Hammering the sensor could permanently damage it.
WARNING
Personal Injury Hazard!
Before working on a vehicle, set the parking brakes, place
the transmission in neutral and block the wheels.
DO NOT work under a vehicle supported only by jacks.
Always use jack stands under the vehicle.
Stop the engine and remove ignition key when working
under or around the vehicle.
If the work is being performed on the vehicle’s air brake
system, or any auxiliary pressurized air systems, make
certain to drain the air pressure from all reservoirs before
beginning any work on the vehicle.
Failure to follow these warnings can cause serious
personal injury or death.
Fo
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Reference
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