Wheel Speed Sensor: Testing and Inspection

1. Prepare system for remaining checks as follows:
a. Turn ignition switch to Off position.
b. Depress parking brake pedal.

Fig. 19 Check Connector Pin Identification:

c. Connect diagnosis check wiring tool No. 09843-18020 or equivalent, to terminals Ts and E1, Tc and E1 of check connector, Fig. 19.
d. Do not depress brake pedal.
e. Block wheels and start engine.
2. Ensure the warning light changes from flashing to lighting up for one second, then to flashing again when the following operations are performed:
a. Depress the brake pedal.
b. Release parking brake, then depress parking brake again.
c. With brake pedal depressed, shift transmission lever to another position other than ``P'' or ``N.'' (Only on vehicles with TRAC)
3. Check speed sensor signal as follows:
a. Release parking brake.
b. Drive vehicle straight forward.

Fig. 20 Speed Sensor Signal Chart:

c. Ensure anti-lock warning light flashes or lights up when vehicle is at speeds indicated in Fig. 20.
d. Check the output voltage of the speed sensor at a vehicle speed of 2.5-3.7 mph.
e. Check the change in output voltage of the speed sensor at a vehicle speed of 28-43 mph and at 68-81 mph.
f. Stop vehicle.

Fig. 21 Speed Sensor Fault (trouble) Codes:

Fig. 18 Speed Sensor Fault (trouble) Code Chart:

g. Read number of flashes, Fig. 21, of the anti-lock warning light and refer to Fig. 18, for diagnostic (trouble) code identification.
h. The warning light will go On for .125 second and Off for .125 second. If two or more codes are identified at the same time, the lowest numbered code will be displayed first.