DTC 28 REAR LEFT ABNORMAL ABS WHEEL SPEED SENSOR SIGNAL

/ 9-2X (9346) / 2005 / 5. Brakes / ABS (DIAGNOSTICS) / Diagnostic Procedure with Diagnostic Trouble Code (DTC) / Fault diagnosis, fault codes / DTC 28 REAR LEFT ABNORMAL ABS WHEEL SPEED SENSOR SIGNAL

DIAGNOSIS:

•

Faulty ABS wheel speed sensor signal (noise, irregular signal, etc.)

•

Faulty harness/connector

TROUBLE SYMPTOM:

ABS does not operate.

WIRING DIAGRAM:

CHECK OUTPUT OF ABS WHEEL SPEED SENSOR USING Vehicle Diagnostic Interface.

Select “Current data display & Save” on the Vehicle Diagnostic Interface.

Read the ABS wheel speed sensor output corresponding to faulty system in the Vehicle Diagnostic Interface data display mode.

Does the speed indicated on display change in response to speedometer reading during acceleration/deceleration when the steering wheel is in straight-ahead position?

Yes

CHECK POOR CONTACT IN CONNECTORS.

Turn the ignition switch to OFF.

Is there poor contact in connectors between ABSCM&H/U and ABS wheel speed sensor?

Yes

Repair the connector.

CHECK SOURCES OF SIGNAL NOISE.

Is the car telephone or wireless transmitter properly installed?

Yes

Properly install the car telephone or wireless transmitter.

CHECK SOURCES OF SIGNAL NOISE.

Are noise sources (such as an antenna) installed near the sensor harness?

Yes

Install the noise sources apart from sensor harness.

CHECK ABSCM&H/U.

Connect all connectors.

Erase the memory.

Perform the inspection mode.

Read out the DTC.

Is the same DTC as in the current diagnosis still being output?

Yes

Replace the ABSCM&H/U.

CHECK ANY OTHER DTC APPEARANCE.

Are other DTCs being output?

Yes

Proceed with the diagnosis corresponding to DTC.

A temporary noise interference.

CHECK INSTALLATION OF ABS WHEEL SPEED SENSOR.

Are the ABS wheel speed sensor installation bolts tightened 33 Nm (3.3 kgf-m, 24 ft-lb)?

Yes

Tighten the ABS wheel speed sensor installation bolts securely.

CHECK ABS WHEEL SPEED SENSOR GAP.

Measure the tone wheel to ABS wheel speed sensor piece gap over entire perimeter of wheel.

Is the gap as following value? Front wheel: 0.3 — 0.8 mm (0.012 — 0.031 in) Rear wheel: 0.7 — 1.2 mm (0.028 — 0.047 in)

Yes

•

Adjust the gap.

•

Note
Adjust the gap using spacer (Part No. 32009555). If the spacers cannot correct gap, replace worn sensor or worn tone wheel.

PREPARE OSCILLOSCOPE.

Is an oscilloscope available?

Yes

CHECK ABS WHEEL SPEED SENSOR SIGNAL.

Raise all four wheels off ground.

Turn the ignition switch to OFF.

Connect the oscilloscope to the connector.

Turn the ignition switch to ON.

Rotate the wheels and measure voltage at specified frequency.

Note
When this inspection is completed, the ABSCM&H/U sometimes stores DTC 29 or DTC 56.

Connector & terminal

DTC 22

(B15) No. 1 (+) — No. 2 (−):

DTC 24

(B62) No. 20 (+) — No. 24 (−):

DTC 26

(B99) No. 10 (+) — No. 9 (−):

DTC 28

(B99) No. 5 (+) — No. 4 (−):

Is the waveform pattern on oscilloscope as shown in the figure?

Yes

CHECK CONTAMINATION OF ABS WHEEL SPEED SENSOR OR TONE WHEEL.

Remove the disc rotor or drum from hub in accordance with DTC.

Is the ABS wheel speed sensor piece or tone wheel contaminated by dirt or other foreign matter?

Yes

Thoroughly remove dirt or other foreign matter.

CHECK DAMAGE OF ABS WHEEL SPEED SENSOR OR TONE WHEEL.

Are there broken or damaged in the ABS wheel speed sensor piece or tone wheel?

Yes

Replace the ABS wheel speed sensor or tone wheel. Front: Rear: and Front: Rear:

CHECK TONE WHEEL RUNOUT.

Measure the tone wheel runout.

Is the runout less than 0.05 mm (0.0020 in)?

Yes

Replace the tone wheel. Front: Rear:

CHECK RESISTANCE OF ABS WHEEL SPEED SENSOR.

Turn the ignition switch to OFF.

Disconnect the connector from ABS wheel speed sensor.

Measure the resistance between ABS wheel speed sensor connector terminals while shaking the harness lightly.

Terminals

Front RH No. 1 — No. 2:

Front LH No. 1 — No. 2:

Rear RH No. 1 — No. 2:

Rear LH No. 1 — No. 2:

Is the resistance as following value? Front: 1 — 1.5 kΩ Rear: 1.025 — 1.265 kΩ

Yes

Replace the ABS wheel speed sensor. Front: Rear:

CHECK GROUND SHORT OF ABS WHEEL SPEED SENSOR.

Measure the resistance between ABS wheel speed sensor and chassis ground.

Terminals

Front RH No. 1 — Chassis ground:

Front LH No. 1 — Chassis ground:

Rear RH No. 1 — Chassis ground:

Rear LH No. 1 — Chassis ground:

Is the resistance more than 1 MΩ?

Yes

Replace the ABS wheel speed sensor. Front: Rear:

CHECK HARNESS/CONNECTOR BETWEEN ABSCM&H/U AND ABS WHEEL SPEED SENSOR.

Connect the connector to ABS wheel speed sensor.

Disconnect the connector from ABSCM& H/U.

Measure the resistance at ABSCM&H/U connector terminals.

Connector & terminal

DTC 22

(B301) No. 6 — No. 5:

DTC 24

(B301) No. 1 — No. 16:

DTC 26

(B301) No. 19 — No. 4:

DTC 28

(B301) No. 3 — No. 2:

Is the resistance as following value? Front: 1 — 1.5 kΩ Rear: 1.025 — 1.265 kΩ

Yes

Repair the harness/connector between ABSCM&H/U and ABS wheel speed sensor.

CHECK GROUND SHORT OF HARNESS.

Measure the resistance between ABSCM&H/U connector and chassis ground.

Connector & terminal

DTC 22

(B301) No. 6 — Chassis ground:

DTC 24

(B301) No. 1 — Chassis ground:

DTC 26

(B301) No. 19 — Chassis ground:

DTC 28

(B301) No. 3 — Chassis ground:

Is the resistance more than 1 MΩ?

Yes

Repair the harness/connector between ABSCM&H/U and ABS wheel speed sensor.

CHECK GROUND CIRCUIT OF ABSCM&H/U.

Measure the resistance between ABSCM&H/U and chassis ground.

Connector & terminal

(B301) No. 15 — Chassis ground:

Is the resistance less than 0.5 Ω?

Yes

Repair the ABSCM&H/U ground harness.

CHECK POOR CONTACT IN CONNECTORS.

Is there poor contact in connectors between ABSCM&H/U and ABS wheel speed sensor?

Yes

Repair the connector.

CHECK SOURCES OF SIGNAL NOISE.

Is the car telephone or the wireless transmitter properly installed?

Yes

Properly install the car telephone or wireless transmitter.

CHECK SOURCES OF SIGNAL NOISE.

Are noise sources (such as an antenna) installed near the sensor harness?

Yes

Install the noise sources apart from sensor harness.

CHECK ABSCM&H/U.

Connect all connectors.

Erase the memory.

Perform the inspection mode.

Read out the DTC.

Is the same DTC as in the current diagnosis still being output?

Yes

Replace the ABSCM&H/U.

CHECK ANY OTHER DTC APPEARANCE.

Are other DTCs being output?

Yes

Proceed with the diagnosis corresponding to DTC.

•

A temporary noise interference.

•

Note
Although the ABS warning light remains illuminating at this point, this is a normal condition. Vehicle must be driven at approx. 12 km/h (7.46 MPH) or faster to turn off ABS warning light. Make sure that the ABS warning light goes off after driving vehicle.

DTC 28 REAR LEFT ABNORMAL ABS WHEEL SPEED SENSOR SIGNAL

CHECK OUTPUT OF ABS WHEEL SPEED SENSOR USING Vehicle Diagnostic Interface.

Does the speed indicated on display change in response to speedometer reading during acceleration/deceleration when the steering wheel is in straight-ahead position?

CHECK POOR CONTACT IN CONNECTORS.

Is there poor contact in connectors between ABSCM&H/U and ABS wheel speed sensor?

CHECK SOURCES OF SIGNAL NOISE.

Is the car telephone or wireless transmitter properly installed?

CHECK SOURCES OF SIGNAL NOISE.

Are noise sources (such as an antenna) installed near the sensor harness?

CHECK ABSCM&H/U.

Is the same DTC as in the current diagnosis still being output?

CHECK ANY OTHER DTC APPEARANCE.

Are other DTCs being output?

CHECK INSTALLATION OF ABS WHEEL SPEED SENSOR.

Are the ABS wheel speed sensor installation bolts tightened 33 Nm (3.3 kgf-m, 24 ft-lb)?

CHECK ABS WHEEL SPEED SENSOR GAP.

Is the gap as following value? Front wheel: 0.3 — 0.8 mm (0.012 — 0.031 in) Rear wheel: 0.7 — 1.2 mm (0.028 — 0.047 in)

PREPARE OSCILLOSCOPE.

Is an oscilloscope available?

CHECK ABS WHEEL SPEED SENSOR SIGNAL.

Is the waveform pattern on oscilloscope as shown in the figure?

CHECK CONTAMINATION OF ABS WHEEL SPEED SENSOR OR TONE WHEEL.

Is the ABS wheel speed sensor piece or tone wheel contaminated by dirt or other foreign matter?

CHECK DAMAGE OF ABS WHEEL SPEED SENSOR OR TONE WHEEL.

Are there broken or damaged in the ABS wheel speed sensor piece or tone wheel?

CHECK TONE WHEEL RUNOUT.

Is the runout less than 0.05 mm (0.0020 in)?

CHECK RESISTANCE OF ABS WHEEL SPEED SENSOR.

Is the resistance as following value? Front: 1 — 1.5 kΩ Rear: 1.025 — 1.265 kΩ

CHECK GROUND SHORT OF ABS WHEEL SPEED SENSOR.

Is the resistance more than 1 MΩ?

CHECK HARNESS/CONNECTOR BETWEEN ABSCM&H/U AND ABS WHEEL SPEED SENSOR.

Is the resistance as following value? Front: 1 — 1.5 kΩ Rear: 1.025 — 1.265 kΩ

CHECK GROUND SHORT OF HARNESS.

Is the resistance more than 1 MΩ?

CHECK GROUND CIRCUIT OF ABSCM&H/U.

Is the resistance less than 0.5 Ω?

CHECK POOR CONTACT IN CONNECTORS.

Is there poor contact in connectors between ABSCM&H/U and ABS wheel speed sensor?

CHECK SOURCES OF SIGNAL NOISE.

Is the car telephone or the wireless transmitter properly installed?

CHECK SOURCES OF SIGNAL NOISE.

Are noise sources (such as an antenna) installed near the sensor harness?

CHECK ABSCM&H/U.

Is the same DTC as in the current diagnosis still being output?

CHECK ANY OTHER DTC APPEARANCE.

Are other DTCs being output?

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