Circuit Description
The wheel speed sensor produces an AC voltage whose amplitude and frequency
vary, depending on the velocity of the wheel. The EBTCM uses this voltage signal
to calculate the wheel speed.
Conditions for setting the DTC
DTC C0040 will set if the following conditions exist:
| • | The right front wheel speed circuit is open, grounded, or shorted to the
battery |
| • | The right front wheel speed = zero, while the other wheel speeds are greater
than 40 km/h (25 mph) for 10 ms. |
| • | This code can set anytime after the key is turned to the RUN position. |
When the DTC sets, the EBTCM will disable the ABS and the Traction Control and
turn on the antilock telltale.
If two or more wheel speed faults occur, dynamic rear proportioning (DRP) is
disabled for the entire ignition cycle.
Diagnostic Aids
Inspect the wiring, the components, and the connector for the following conditions:
| • | Corrosion in the connectors/terminals |
| • | Burned, chafed or pinched wires |
| • | A broken wire inside the insulation |
Possible causes for DTC C0040 to set are:
| • | Damaged or missing teeth on the wheel speed sensor ring. |
| • | Large grooves or gouges, or build-up of foreign material in the gaps between
the wheel speed sensor ring teeth. |
| • | A worn front hub bearing assembly, or a worn inner axle bearing which
could allow the sensor to toothed ring gap to change excessively. |
DTC C0040
DTC C0040 (cont'd)
