Circuit Description
The toothed wheel generates a voltage pulse as it moves past the wheel speed sensor. Each tooth-gap-tooth series on the wheel generates the pulses. The electronic brake control module (EBCM) uses the frequency of these pulses to determine wheel speed. The voltage generated depends on the air gap between the wheel speed sensor and the toothed wheel, and on the wheel speed.
This DTC will set when the EBCM cannot identify which wheel speed sensor is causing the malfunction. It is necessary to inspect all wheel speed sensors and associated wiring to determine the cause of the DTC.
Conditions for Setting the DTC
| • | Incorrect number of teeth on the toothed wheel |
| • | Damaged or broken teeth on the toothed wheel |
| • | Discontinuity or short in the wheel speed sensor wiring |
Action Taken When the DTC Sets
Antilock brake system (ABS) action is disabled and the ABS warning lamp is ON.
Diagnostic Aids
DTC C0245 may be set by running the scan tool auto test if the throttle angle readings are not updating while in the data list mode. If this is the case, clear the DTCs, disconnect the scan tool, and road test the vehicle to at least 12 km/h (7 mph) to see if the DTC resets.
Inspect the toothed wheels for any large grooves, gouges, marks, etc. that might influence the tooth's signal at the wheel speed sensor. Also inspect for a buildup of foreign material in the gaps between the teeth in the toothed wheel. A buildup of foreign material may cause this malfunction.
A badly worn hub/bearing assembly may cause this malfunction. The wheel speed sensor-to-toothed wheel air gap may change excessively due to bearing play. If an improper rear hub assembly or front outer constant velocity joint is installed, one with a toothed wheel containing the incorrect number of teeth, this DTC can set. Be sure that the front and the rear toothed wheel have 47 and 29 teeth.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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This step begins the examination of the front wheel speed sensors.
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This step inspects for a problem with one of the front toothed rings.
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This step inspects the front wheel speed sensors.
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This step inspects for shorts in a front wheel speed sensor harness.
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This step inspects for opens in a front wheel speed sensor harness.
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This step begins an inspection of the rear wheel speed sensors.
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This step inspects for a problem with one of the rear toothed rings.
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This step inspects the rear wheel speed sensors.
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This step inspects for shorts in a rear wheel speed sensor harness.
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This step inspects for opens in a rear wheel speed sensor harness.
Step | Action | Values | Yes | No | ||||
|---|---|---|---|---|---|---|---|---|
Visually inspect the wiring for the front wheel speed sensors. Is there any damage? | -- | Go to Step 2 | Go to Step 3 | |||||
2 | Verify that the correct outer constant velocity (CV) joints are installed on the vehicle. The front speed rings have 47 teeth and the rear speed rings have 29 teeth. Did you complete the action? | -- | System OK | -- | ||||
Inspect fuse EF2 in the engine fuse block. Is fuse EF2 open? | -- | Go to Step 4 | Go to Step 5 | |||||
4 | Replace fuse EF2. Did you complete the replacement? | -- | System OK | -- | ||||
Does the resistance measure within the specified range for both wheel speed sensors? | 1280-1920 ohms | Go to Step 7 | Go to Step 6 | |||||
6 | Replace the faulty wheel speed sensor. Did you complete the replacement? | -- | System OK | -- | ||||
Is there any short circuit in either wheel speed sensor harness? | -- | Go to Step 8 | Go to Step 9 | |||||
8 | Repair the short circuit in the wiring or from a wiring harness to ground. Did you complete the repair? | -- | System OK | -- | ||||
Test the continuity of the wiring in both front wheel speed sensor circuits between the ABS connector and the wheel speed sensor wheel speed sensor connector on each side of the vehicle.
Is the continuity good for both harnesses? | -- | Go to Step 11 | Go to Step 10 | |||||
10 | Repair the discontinuity found in the front wheel speed sensor harness. Did you complete the repair? | -- | System OK | -- | ||||
Is there any damage? | -- | Go to Step 12 | Go to Step 13 | |||||
12 | Repair or replace components as required. Did you find and correct the condition? | -- | System OK | -- | ||||
Remove each wheel speed sensor from the rear knuckles and inspect the toothed ring through the wheel speed sensor mounting holes.
Is there any damage or other fault with either speed ring? | -- | Go to Step 14 | Go to Step 15 | |||||
14 | Replace the rear wheel hub with the proper unit. Did you complete the replacement? | -- | System OK | -- | ||||
Does the resistance measure within the specified range for both wheel speed sensors? | 1280-1920 ohms | Go to Step 17 | Go to Step 16 | |||||
16 | Replace the faulty wheel speed sensor. Did you complete the replacement? | -- | System OK | -- | ||||
Is there any short circuit in either wheel speed sensor harness? | -- | Go to Step 18 | Go to Step 19 | |||||
18 | Repair the short circuit in the wiring or from a wire to ground. Did you complete the repair? | -- | System OK | -- | ||||
Test the continuity of the wiring in both rear wheel speed sensor circuits between the ABS connector and the wheel speed sensor wheel speed sensor connector on each side of the vehicle.
Is continuity good for both harnesses? | -- | Go to Step 21 | Go to Step 20 | |||||
20 | Repair the discontinuity found in the rear wheel speed sensor wheel speed sensor harness or connector C110. Did you complete the repair? | -- | System OK | -- | ||||
21 | Replace the ABS unit. Did you complete the replacement? | -- | System OK | -- |
