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Without Scan Tool

  1. Turn ignition off. Using a fused jumper wire or Service Connector (SST 09843-18020), connect Data Link Connector No. 1 (DLC1) terminals Ts and E1. See Figure. DLC1 is located in engine compartment, next to oil fill cap. Start engine. ABS warning light should blink once every .13 second. If ABS warning light does not blink, check ABS warning light circuit. See ABS WARNING LIGHT CIRCUIT  under SYSTEM TESTS.
  2. Drive vehicle at 28 MPH or greater for several seconds in a straight line. Stop vehicle. Using another fused jumper wire or Service Connector (SST 09843-18020), connect DLC1 terminals Tc and E1. There should now be 2 jumper wires. See Figure.
  3. Observe ABS warning light. If system is normal, ABS warning light will blink every .25 second. If system is malfunctioning, ABS warning light will flash codes. Identify DTC and probable cause. See SPEED SENSOR DIAGNOSTIC TROUBLE CODE IDENTIFICATION  table. Repair as necessary. Turn ignition off. Remove fused jumper wires or Service Connectors (SST 09843-18020), from DLC1.
SPEED SENSOR DIAGNOSTIC TROUBLE CODE IDENTIFICATION

Lexus Scan Tool DTC/ABS Warning Light DTC Description Probable Cause
C1271/71 Right Front Speed Sensor Signal Voltage Low Defective Right Front Speed Sensor, Incorrect Sensor Installation Or Defective Sensor Rotor
C1272/72 Left Front Speed Sensor Signal Voltage Low Defective Left Front Speed Sensor, Incorrect Sensor Installation Or Defective Sensor Rotor
C1273/73 Right Rear Speed Sensor Signal Voltage Low Defective Right Rear Speed Sensor, Incorrect Sensor Installation Or Defective Sensor Rotor
C1274/74 Left Rear Speed Sensor Signal Voltage Low Defective Left Rear Speed Sensor, Incorrect Sensor Installation Or Defective Sensor Rotor
C1275/75 Abnormal Change In Output Signal Voltage From Right Front Speed Sensor Defective Right Front Sensor Rotor
C1276/76 Abnormal Change In Output Signal Voltage From Left Front Speed Sensor Defective Left Front Sensor Rotor
C1277/77 Abnormal Change In Output Signal Voltage From Right Rear Speed Sensor Defective Right Rear Sensor Rotor
C1278/78 Abnormal Change In Output Signal Voltage From Left Rear Speed Sensor Defective Left Rear Sensor Rotor
C1279/79 Defective Deceleration Sensor Defective Deceleration Sensor Or Sensor Not Installed Proberly
C1281/81 Faulty Master Cylinder Pressure Sensor Output Signal Defective Master Cylinder Pressure Sensor