Wheel Speed Sensor: Testing and Inspection
Checking pulse wheel lateral runout
Special tools:
999 9683 ROCKER INDICATOR 0-0.8 MM 999 9683 Rocker Indicator 0-0.8 mm
999 9684 DIAL INDICATOR 0-10 MM 999 9684 Dial Indicator 0-10 mm
999 9696 MAGNETIC BASE 999 9696 Magnetic Base
Front wheel brakes
Checking play in front wheel bearings
Raise car so that wheels can rotate freely.
Check the bearing for play and replace if necessary.
Removing front wheel sensor
Remove hub cap and wheel.
Note! Carefully clean the sensor and connector before removal.
Remove mounting bolt and pull out sensor.
Clean hole.
Checking lateral runout in the front wheel pulse wheel visually
Rotate the drive shaft slowly and visually check the pulse wheel for vertical or lateral runout.
Press the pulse wheel firmly down onto the drive shaft if there is any runout. See Front pulse wheel replacement Front Pulse Wheel Replacement.
Check pulse wheel visually again for runout. Replace pulse wheel and/or drive shaft if there is still runout.
See Front pulse wheel replacement Front Pulse Wheel Replacement or Removing/fitting the rear pulse wheel Removing/Fitting The Rear Pulse Wheel.
Measuring vertical runout in the front wheel pulse wheel
Locate holder 999 9696 MAGNETIC BASE 999 9696 Magnetic Base and dial gauge 999 9684 DIAL INDICATOR 0-10 MM 999 9684 Dial Indicator 0-10 mm with a measuring probe (100 mm long).
Locate measuring probe and measure run out over the whole ring.
If run out is more than 0.15 mm, the pulse wheel must be replaced and the drive shaft checked. See Front pulse wheel replacement Front Pulse Wheel Replacement or Removing/fitting the rear pulse wheel Removing/Fitting The Rear Pulse Wheel.
Installing front wheel sensor
See Front wheel sensor, replacement Front Wheel Sensor, Replacement.
Rear wheel brakes
Checking clearance in rear wheel bearings
Raise car so that wheels can rotate freely.
Check bearings for play and replace if necessary.
Checking rear wheel pulse wheel visually for lateral runout
Remove
- hub cap and wheel.
- brake caliper and brake disc, see Replacement of rear brake disc Brake Disc Rear, Replacing.
Rotate hub slowly and inspect pulse wheel visually for runout.
Check pulse wheel mounting.
Check pulse wheel again for runout.
Check runout in hub.
Replace pulse wheel and/or brake disc hub if there is runout.
Measuring runout in the rear wheel pulse wheel
Locate holder 999 9696 MAGNETIC BASE 999 9696 Magnetic Base and dial gauge 999 9683 ROCKER INDICATOR 0-0.8 MM 999 9683 Rocker Indicator 0-0.8 mm
Locate measuring probe and measure run out over the whole ring.
If run out is exceeds 0.13 mm, replace the pulse wheel. See Removing/fitting the rear pulse wheel Removing/Fitting The Rear Pulse Wheel.
Install
- brake disc and caliper, see Replacement of rear brake disc Brake Disc Rear, Replacing.
- hub cap and wheel, see Brake pads rear, replacement Brake Pads Rear, Replacing.