Circuit Description
The Electronic Brake Control Module (EBCM) receives right rear wheel speed sensor voltage signal through terminal 15 and terminal 16. As a toothed ring passes by the wheel speed sensor, changes in the electromagnetic field cause the wheel speed sensor to produce a small AC voltage signal. This signal's frequency is proportional to the wheel speed.
Conditions for Clearing the DTC
| • | DTC C0051 will set when the EBCM detects a sudden change in the right rear wheel speed determined to be unreasonable. |
| • | DTC C0051 can be set anytime. |
Action Taken When the DTC Sets
| • | A malfunction DTC stores |
| • | The ABS disables |
| • | The ABS warning indicator turns ON |
Conditions for Clearing the DTC
The condition responsible for setting the DTC no longer exists and the Scan Tool Clear DTCs function is used. If the right rear wheel speed signal is still incorrect, DTC C0051 will set again as a current DTC and the ABS warning indicator remains ON.
Diagnostic Aids
Inspect for the following when diagnosing this part of the Antilock Brake System (ABS):
| • | Loose right rear wheel speed sensor |
| • | Worn right rear suspension and or drivetrain components |
| • | Right rear wheel speed sensor physically damaged |
| • | Right rear wheel speed sensor reluctor wheel toothed ring damaged |
Perform a careful visual inspection of the following items:
| • | The right rear wheel speed sensor toothed ring |
| • | The right rear wheel bearing |
| • | The right rear wheel speed sensor |
An intermittent malfunction is most likely caused by a poor connection rubbed thorough wire insulation or a wire that is broken inside the insulation.
If the customer comments reflect that the ABS indicator lamp is ON only during humid conditions (rain, snow, vehicle wash), thoroughly inspect the right rear wheel speed sensor circuitry for signs of water intrusion.
Thoroughly inspect any circuitry that is suspected or causing the intermittent complaint for the following conditions:
| • | Backed-out terminals |
| • | Improper mating |
| • | Broken locks |
| • | Improperly formed or damaged terminals |
| • | Poor terminal to wiring connections |
| • | Physical damage to the wiring harness |
| Important: Wheel speed sensor resistance increases with an increase in sensor temperature. When measuring for a short to ground in a wheel speed sensor wiring circuit, manually switch the J 39200 (Digital Multimeter) to the Meg-Ohms range. This will ensure a high resistance short to ground can be found. See J 39200 owners manual. |
Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
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Tests electrical circuits between the wheel speed sensor and the Electronic Brake Control Module (EBCM). If an open, short to ground, or short to voltage is present circuit repairs must be done first.
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Excessive tire and or wheel assembly waddle and/or play can set this DTC due to excessive wheel speed fluctuations.
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Tests for a physically damaged wheel speed sensor.
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Tests for a physically damaged wheel speed sensor reluctor wheel.
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Tests the internal resistance of the wheel speed sensor for proper values.
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Tests the voltage output performance of the wheel speed sensor.
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Tests for wheel speed sensor circuits shorted together.
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Tests for poor connections at electrical connectors.
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Determines whether the condition is intermittent and not due to a malfunctioning EBCM.
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Performs Electronic Brake Control Module (EBCM) repair confirmation after completed repairs.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Was the Diagnostic System Check performed? | -- | Go to Step 2 | |
Is DTC C0050 set as current or history DTC? | -- | Go to Step 3 | ||
Test the right rear wheel bearing for excessive play. Refer to Rear Suspension for specifications. Is the left rear wheel bearing play out of specifications? | -- | Go to Step 11 | Go to Step 4 | |
Does the right rear wheel speed sensor have signs of any physical damage? | -- | Go to Step 12 | Go to Step 5 | |
Inspect the right rear wheel speed sensor reluctor wheel for physical damage. Does the right rear wheel speed sensor reluctor wheel have signs of physical damage? | -- | Go to Step 13 | Go to Step 6 | |
Is the resistance within the specified range? | 1120-2520 ohms | Go to Step 7 | Go to Step 8 | |
Is the voltage equal to or greater than the specified voltage? | 100 mV | Go to Step 9 | Go to Step 12 | |
Is the resistance equal to the specified value? | OL (Infinite) | Go to Step 12 | Go to Step 14 | |
Did you detect signs of poor terminal contact, corrosion, or damaged terminals? | -- | Go to Step 15 | Go to Step 10 | |
Does DTC C0051 set as a current DTC? | -- | Go to Step 16 | ||
11 | Repair the excessive right rear wheel bearing play. Refer to Rear Wheel Bearing and Hub Replacement in Rear Suspension for service procedure. Is the repair complete? | -- | Go to Step 17 | -- |
12 | Replace the right rear wheel speed sensor. Refer to Rear Wheel Speed Sensor Replacement . Is the repair complete? | -- | Go to Step 17 | -- |
13 | Replace the right rear wheel hub and bearing. Refer to Rear Wheel Bearing and Hub Replacement in Rear Suspension. Is the repair complete? | -- | Go to Step 17 | -- |
14 | Repair the damaged wiring harness that caused the short between the YEL and BRN wires. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Step 17 | -- |
15 | Repair or replace wiring, terminals, or connectors that exhibit signs of damage as necessary. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Step 17 | -- |
16 | Replace the brake pressure modulator valve assembly. Refer to Brake Pressure Modulator Valve Assembly Replacement . Is the action complete? | -- | -- | |
Is the ABS Warning Indicator ON? | -- | -- |
