WABCO 400 500 320 0, Maintenance Manual

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Component Replacement
7.1 Wheel Speed Sensor
7.1.1 How to Remove a Sensor
1. Follow the trailer manufacturer’s instructions to back off the slack adjuster and remove the tire, wheel
and drum.
2. Hold the sensor, not the cable, and use a twisting motion to pull the sensor out of its mounting block.
3. Remove the spring clip from the mounting block.
4. Remove any fasteners that hold the sensor cable to other components.
5. Disconnect the sensor cable from the extension cable.
7.1.2 How to Install a Sensor
Sensor locations vary according to suspension types. Typically, a spring suspension has sensors on the
forward axle, and an air suspension has sensors on the rear axle.
1. Apply a mineral oil-based grease that contains molydisul fi de to the sensor spring clip and to the
body of the sensor. The grease must be anti-corrosive and contain adhesive properties that will
continuously endure temperatures from –40° to 300°F (–40° to 150°C). The use of non-approved
lubricants is at your own risk. Please note that non-approved lubricants can reduce the performance
of the parts or lead to damage of the product that may not be covered under warranty.
2. Push the spring clip into the sensor holder from the inboard side, until the spring clip tabs are against
the sensor holder. Push the sensor into the spring clip as far as possible. Figure 7.1.
Fig. 7.1
SENSOR
HOLDER
SPRIN G
CLIP
SPRIN G
CLIP TAB
SENSOR
1002100 b
3. Route the sensor cable toward the brake chamber, over the brake spider, and behind the axle. Secure
the cable to the axle between the brake spider and the suspension brackets. Continue to route the
sensor cable behind the spring seats. Secure the cable to the axle 3 inches from the molded sensor
plug. Figure 7.2.
Fig. 7.2
3"
SENSOR
CABLE
1002101b