Code 22, 24, 26, 28: Abnormal Abs Sensor (Abnormal Abs Sensor Signal)

DIAGNOSIS:

Faulty ABS sensor signal (noise, irregular signal, etc.)
Faulty harness/connector

TROUBLE SYMPTOM:

ABS does not operate.

WIRING DIAGRAM:

Fig 1: Wiring Diagram

8I1: CHECK INSTALLATION OF ABS SENSOR.
Tightening torque: 32+/-10 N.m (3.3+/-1.0 kg-m, 24+/-7 ft-lb)

CHECK: Are the ABS sensor installation bolts tightened securely?
1. YES: Go to step 8I2.
2. NO: Tighten ABS sensor installation bolts securely.
8I2: CHECK TROUBLE CODE.
CHECK: Is the trouble code 26 and/or 28?
1. YES: Go to step 8I3.
2. NO: Go to step 8I4: CHECK ABS SENSOR GAP. .
8I3: CHECK INSTALLATION OF REAR TONE WHEEL.
Tightening torque: 13+/-3 N.m (1.3+/-0.3 kg-m, 9+/-2.2 ft-lb)

CHECK: Are the rear tone wheel installation bolts tightened securely?
1. YES: Go to step 8I4.
2. NO: Tighten rear tone wheel installation bolts securely.
8I4: CHECK ABS SENSOR GAP.
Measure tone wheel to pole piece gap over entire perimeter of the wheel.

Fig 2: Measuring Tone Wheel To Pole Piece Gap Over Entire Perimeter Of Wheel

Fig 3: Specifications Tone Wheel To Pole Piece Gap

CHECK: Is the gap within the specifications?
1. YES: Go to step 8I5.
2. NO: Adjust the gap.
NOTE: Adjust the gap using spacer (Part No. 26755AA000). If spacers cannot correct the gap, replace worn sensor or worn tone wheel.
8I5: PREPARE OSCILLOSCOPE.
CHECK: Is an oscilloscope available?
1. YES: Go to step 8I6.
2. NO: Go to step 8I7: CHECK CONTAMINATION OF ABS SENSOR OR TONE WHEEL .
8I6: CHECK ABS SENSOR SIGNAL.
1. Raise all four wheels of ground.
2. Turn ignition switch to OFF.
3. Connect the oscilloscope to the connector.
4. Turn ignition switch to ON.
5. Rotate wheels and measure voltage at specified frequency.
NOTE: When this inspection is completed, the ABSCM & H/U sometimes stores the trouble code 29.

Connector & terminal
1. Trouble code 22 / (B100) No. 5 (+) - No. 14 (-):
2. Trouble code 24 / (B100) No. 7 (+) - No. 16 (-):
3. Trouble code 26 / (F55) No. 6 (+) - No. 7 (-):
4. Trouble code 28 / (F55) No. 1 (+) - No. 2 (-):
Fig 4: Measuring Voltage At Specified Frequency While Rotating Wheels

CHECK: Is oscilloscope pattern smooth, as shown in figure?
1. YES: Go to step 8I10: CHECK RESISTANCE OF FRONT ABS SENSOR .
2. NO: Go to step 8I7.
8I7: CHECK CONTAMINATION OF ABS SENSOR OR TONE WHEEL.
Remove disc rotor or drum from hub in accordance with trouble code.

CHECK: Is the ABS sensor pole piece or the tone wheel contaminated by dirt or other foreign matter?
1. YES: Thoroughly remove dirt or other foreign matter.
2. NO: Go to step 8I8.
8I8: CHECK DAMAGE OF ABS SENSOR OR TONE WHEEL.
CHECK: Are there broken or damaged in the ABS sensor pole piece or the tone wheel?
1. YES: Replace ABS sensor or tone wheel.
2. NO: Go to step 8I9.
8I9: CHECK HUB RUNOUT.
Measure hub runout.

CHECK: Is the runout less than 0.05 mm (0.0020 in)?
1. YES: Go to step 8I10.
2. NO: Repair hub.
8I10: CHECK RESISTANCE OF FRONT ABS SENSOR.
1. Turn ignition switch to OFF.
2. Disconnect connector from front ABS sensor.
3. Measure resistance between front ABS sensor connector terminals.
Terminals
1. RH No. 1 - No. 2:
2. LH No. 1 - No. 2:
Fig 5: Measuring Resistance Between Front ABS Sensor Connector Terminals

CHECK: Is the resistance between 1.0 and 1.5 kohm?
1. YES: Go to step 8I11.
2. NO: Replace front ABS sensor.
8I11: CHECK RESISTANCE OF REAR ABS SENSOR.
1. Turn ignition switch to OFF.
2. Disconnect connector from rear ABS sensor.
3. Measure resistance between rear ABS sensor connector terminals.
Terminals
1. RH No. 1 - No. 2:
2. LH No. 1 - No. 2:
Fig 6: Measuring Resistance Between Rear ABS Sensor Connector Terminals

CHECK: Is the resistance between 0.8 and 1.2 kohm?
1. YES: Go to step 8I12.
2. NO: Replace rear ABS sensor.
8I12: CHECK GROUND SHORT OF ABS SENSOR.
Measure resistance between ABS sensor and chassis ground.

Terminals
1. Front RH No. 1 - Chassis ground:
2. Front LH No. 1 - Chassis ground:
3. Rear RH No. 1 - Chassis ground:
4. Rear LH No. 1 - Chassis ground:
Fig 7: Measuring Resistance Between ABS Sensor & Chassis Ground

CHECK: Is the resistance more than 1 Mohm?
1. YES: Go to step 8I13.
2. NO: Replace ABS sensor, see ABS SENSOR .
8I13: CHECK TROUBLE CODE.
CHECK: Is the trouble code 22 and/or 24?
1. YES: Go to step 8I14.
2. NO: Go to step 8I15: CHECK HARNESS/CONNECTOR BETWEEN ABSCM & H/U AND ABS SENSOR .
8I14: CHECK HARNESS/CONNECTOR BETWEEN ABSCM & H/U AND ABS SENSOR.
1. Connect connector to ABS sensor.
2. Disconnect connector from ABSCM & H/U.
3. Measure resistance at ABSCM & H/U connector terminals.
Connector & terminal
1. Trouble code 22 / (F49) No. 11 - No. 12:
2. Trouble code 24 / (F49) No. 9 - No. 10:
Fig 8: Measuring Resistance At ABSCM & H/U Connector Terminals

CHECK: Is the resistance between 1.0 and 1.5 kohm?
1. YES: Go to step 8I16: CHECK GROUND SHORT OF HARNESS .
2. NO: Repair harness/connector between ABSCM & H/U and ABS sensor.
8I15: CHECK HARNESS/CONNECTOR BETWEEN ABSCM & H/U AND ABS SENSOR.
1. Connect connector to ABS sensor.
2. Disconnect connector from ABSCM & H/U.
3. Measure resistance at ABSCM & H/U connector terminals.
Connector & terminal
1. Trouble code 26 / (F49) No. 13 - No. 15:
2. Trouble code 28 / (F49) No. 7 - No. 8:
Fig 9: Measuring Resistance At ABSCM & H/U Connector Terminals

CHECK: Is the resistance between 0.8 and 1.2 kohm?
1. YES: Go to step 8I16.
2. NO: Repair harness/connector between ABSCM & H/U and ABS sensor.
8I16: CHECK GROUND SHORT OF HARNESS.
Measure resistance between ABSCM & H/U connector and chassis ground.

Connector & terminal
1. Trouble code 22 / (F49) No. 11 - Chassis ground:
2. Trouble code 24 / (F49) No. 9 - Chassis ground:
3. Trouble code 26 / (F49) No. 13 - Chassis ground:
4. Trouble code 28 / (F49) No. 7 - Chassis ground:
Fig 10: Measuring Resistance Between ABSCM & H/U Connector & Chassis Ground

CHECK: Is the resistance more than 1 Mohm?
1. YES: Go to step 8117.
2. NO: Repair harness/connector between ABSCM & H/U and ABS sensor.
8117: CHECK GROUND CIRCUIT OF ABSCM & H/U.
Measure resistance between ABSCM & H/U and chassis ground.

Connector & terminal
1. (F49) No. 23 - Chassis ground:
Fig 11: Measuring Resistance Between ABSCM & H/U & Chassis Ground

CHECK: Is the resistance less than 0.5 ohm?
1. YES: Go to step 8118.
2. NO: Repair ABSCM & H/U ground harness.
8118: CHECK POOR CONTACT IN CONNECTORS.
CHECK: Is there poor contact in connectors between ABSCM & H/U and ABS sensor?
1. YES: Repair connector.
2. NO: Go to step 8119.
8119: CHECK SOURCES OF SIGNAL NOISE.
CHECK: Is the car telephone or the wireless transmitter properly installed?
1. YES: Go to step 8120.
2. NO: Properly install the car telephone or the wireless transmitter.
8120: CHECK SOURCES OF SIGNAL NOISE.
CHECK: Are noise sources (such as an antenna) installed near the sensor harness?
1. YES: Install the noise sources apart from the sensor harness.
2. NO: Go to step 8121.
8121: CHECK SHIELD CIRCUIT.
1. Connect all connectors.
2. Measure resistance between shield connector and chassis ground.
Connector & terminal
1. Trouble code 22 / (B100) No. 15 - Chassis ground:
2. Trouble code 24 / (B100) No. 6 - Chassis ground:
3. Trouble code 26 / (F55) No. 8 - Chassis ground:
4. Trouble code 28 / (F55) No. 3 - Chassis ground:
Fig 12: Measuring Resistance Between Shield Connector & Chassis Ground

CHECK: Is the resistance less than 0.5 ohm?
1. YES: Go to step 8122.
2. NO: Repair shield harness.
8122: CHECK ABSCM & H/U.
1. Connect all connectors.
2. Erase the memory.
3. Perform inspection mode.
4. Read out the trouble code.
CHECK: Is the same trouble code as in the current diagnosis still being output?
1. YES: Replace ABSCM & H/U, see ABS CONTROL MODULE AND HYDRAULIC CONTROL UNIT (ABSCM & H/U) .
2. NO: Go to step 8123.
8123: CHECK ANY OTHER TROUBLE CODES APPEARANCE.
CHECK: Are other trouble codes being output?
1. YES: Proceed with the diagnosis corresponding to the trouble code.
2. NO: A temporary noise interference.