Operation CHARM: Car repair manuals for everyone.

C0046











The rear wheel speed sensors monitor speed of each wheel by placing a magnetic coupling next to a toothed ring internal to the rear wheel bearings. The signal frequency changes with wheel speed. This sensor produces a AC signal that the EBTCM uses to calculate wheel speed.

CODE PARAMETERS
DTC C0046 will set if:
- Right front wheel speed changes 16 kph (10 mph) or more in 0.01 seconds.
- The 16 kph (10 mph) change must occur three times with one second between each occurrence.
- Left rear code C0045 is not set.
When the trouble code sets, ABS is disable and the antilock telltale is turned on.
Dynamic rear proportioning (DRP) will have minor degradation unless a RR wheel speed code or a RR apply solenoid code is also set, then DRP is disabled and the RED brake telltale is turned on.

DIAGNOSTIC AIDS
Possible causes for DTC C0046 to set:
- External or internal wheel speed circuit intermit tent open
- Excessive air gap
- Low sensor output
- Loose sensor
- Worn suspension or drive train components
- No air gap (pole strike)
- Damage tooth or teeth on speed ring
- Electrical noise coupled onto wheel speed wire
- Brake switch always off or open
- Wheel speed sensor shorted
- Large grooves or gouges, or guild-up of foreign material in the gaps between the wheel speed sensor ring teeth.
- A worn front hub bearing assembly, or worn inner axle bearing which could allow the sensor to toothed ring gap to change excessively.
When attempting to diagnose an intermittent problem, use the Scan tool to review supplemental diagnostic information. The Supplemental data can be used to duplicate a problem.
Intermittents, shorts or opens suspected to be at the connectors can be detected by using a diagnostic service probe. Voltage can be read on wires without disconnecting any connectors.
Check the tightness of the female grip with a spare male terminal.