FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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C0040

C0040-RIGHT FRONT WHEEL SPEED SENSOR MALFUNCTION (NO SIGNAL/INVALID SIGNAL)













NOTES
^ A worn front hub bearing assembly, or worn inner axle bearing which could allow the sensor to toothed ring gap to change excessively.

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 wheel speed.

DTC PARAMETERS
DTC (20040 will set if the following conditions exist:
^ Right front wheel speed circuit is open, grounded, or shorted to battery.
^ Right front wheel speed = zero, while 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 RIJN position.

When the DTC sets, the EBTCM will disable ABS and 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 wiring, components, and connectors for the following:
^ Poor Connection.
^ Backed-out terminals.
^ Broken connector locks.
^ Corrosion in connectors/terminals.
^ Burned, chafed, or pinched wiring.
^ Broken wire inside insulation.
^ Loose components.

Possible causes for DTC C0040 to set:
^ 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.