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July 1: So it begins. Don't worry, this is not in the correct legal jurisdiction!

Speed Sensor Diagnosis

  1. Turn ignition off. Apply parking brake. Using jumper wires, connect check connector terminals Tc, Ts and E1. See Figure. DO NOT depress brake pedal. Start engine. ANTI-LOCK light should blink once every .125 second. If ANTI-LOCK light does not blink, check ANTI-LOCK light circuit. See ANTI-LOCK LIGHT CIRCUIT charts under DIAGNOSTIC CHARTS.
  2. ANTI-LOCK light should change from blinking every .125 second to illuminating for one second. When brake pedal is depressed or when parking brake is released and then applied, ANTI-LOCK light should change back to blinking every .125 second.
  3. Release parking brake. Drive vehicle at indicated speeds, and ensure ANTI-LOCK light illuminates as described. See ANTI-LOCK LIGHT SPEED SENSOR DIAGNOSIS table.
  4. Stop vehicle. Observe ANTI-LOCK light. If system is normal, ANTI-LOCK light will blink every .125 second. If system is malfunctioning, ANTI-LOCK light will flash codes. Turn ignition off. Remove jumper wires from check connector. Repair as necessary. See SPEED SENSOR DIAGNOSTIC CODES under DIAGNOSIS & TESTING for code diagnosis, or see appropriate chart under DIAGNOSTIC CHARTS.
ANTI-LOCK LIGHT SPEED SENSOR DIAGNOSIS

Vehicle Speed ANTI-LOCK Light
0-2 MPH Blinks (Normal); Illuminates (Abnormal)
2.5-3.7 MPH Illuminates Every Second
4-27 MPH Blinks (Normal); Illuminates (Abnormal)
28-34 MPH Illuminates Every Second
35-67 MPH Blinks (Normal); Illuminates (Abnormal)
68-81 MPH Illuminates Every Second
82 Or More Blinks (Normal); Illuminates (Abnormal)