Abs Function Test

NOTE: BRAKE warning light should remain on if parking brake is applied and ignition is turned on.

Turn ignition on and note operation of ANTI-LOCK indicator light on instrument panel. ANTI-LOCK indicator light should come on for 3 seconds and then go off.
If ANTI-LOCK indicator light does not operate as specified, check for a system malfunction. System malfunction(s) can be detected by different ANTI-LOCK light illumination patterns when ignition switch is turned to ON position. See Fig 1 .
ANTI-LOCK light may illuminate immediately after power is supplied to EBCM, about 15 seconds after engine start, and when a certain specified vehicle speed has been reached. Check points for each malfunction can be narrowed down by knowing timing of light illumination.
In addition, system trouble can be detected because of different illumination patterns when ignition switch is turned to ON position. ANTI-LOCK light stops illuminating when ignition switch is turned off. If fault is still not repaired, ANTI-LOCK light illuminates again with same pattern when ignition switch is turned on.
Go to appropriate diagnosis chart. See Fig 3 through Fig 21 . If pinout checks are necessary, use ABS PINOUT CHECK CHART. See Fig 2 . ANTI-LOCK light will go out when ignition switch is turned to OFF position. If malfunction is not repaired, ANTI-LOCK light illuminates again with same pattern when ignition switch is turned on.
To avoid damaging 35-pin EBCM connector, Pinout Box (J-35592) should be installed on EBCM connector before probing a circuit with Digital Volt-Ohmmeter (J-34029A). Pinout box is to be used with Connector Test Adapter Kit (J-35616).

Fig 1: ABS Diagnosis Using ANTI-LOCK Light Pattern

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Fig 2: ABS Pinout Check Chart

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Fig 3: Chart A-1 Schematic

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Fig 4: Chart A-1 (ANTI-LOCK Light Flashes Twice With Key On)

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Fig 5: Chart A-2 (ANTI-LOCK Light Inoperative With Key On)

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Fig 6: Chart B (ANTI-LOCK Light Remains On After Engine Starts (1 Of 3)

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Fig 7: Chart B (ANTI-LOCK Light Remains On After Engine Starts (2 Of 3)

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Fig 8: Chart B (ANTI-LOCK Light Remains On After Engine Starts (3 Of 3)

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Fig 9: Chart B-1 Schematic

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Fig 10: Chart B-1 Flow Chart (Left Front Wheel Speed Sensor Ckt.)

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Fig 11: Chart B-1 Flow Chart (Left Rear Wheel Speed Sensor Ckt.)

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Fig 12: Chart B-1 Flow Chart (Right Front Wheel Speed Sensor Ckt.)

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Fig 13: Chart B-1 Flow Chart (Right Rear Wheel Speed Sensor Ckt.)

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Fig 14: Chart B-2 Schematic (Wheel Solenoid Valve Ckt.)

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Fig 15: Chart B-2 Flow Chart (Left Front Wheel Solenoid Valve Ckt.)

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Fig 16: Chart B-2 Flow Chart (Right Front Wheel Solenoid Valve Ckt.)

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Fig 17: Chart B-2 Flow Chart (Rear Wheels Solenoid Valve Ckt.)

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Fig 18: Chart B-3 Schematic (Ignition Enable Circuit)

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Fig 19: Chart B-3 Flow Chart (Ignition Enable Circuit)

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Fig 20: Chart B-4 Schematic (Alternator Voltage Monitor Ckt.)

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Fig 21: Chart B-4 Flow Chart (Alternator Voltage Monitor Ckt.)

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Fig 22: Chart B-5 Schematic (Valve Relay Circuit)

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Fig 23: Chart B-5 Flow Chart (Valve Relay Circuit)

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Fig 24: Chart C Schematic (ANTI-LOCK Light On Approximately 15 Seconds After Engine Start While Parking)

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Fig 25: Chart C Flow Chart (ANTI-LOCK Light On Approximately 15 Seconds After Engine Start While Parking)

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Fig 26: Chart D (ANTI-LOCK Light Comes On When Driving)

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Fig 27: Chart D-1 Schematic (Pump Motor Circuit)

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Fig 28: Chart D-1 Flow Chart (Pump Motor Circuit)

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Fig 29: Chart D-2 Schematic ("G" Sensor Circuit)

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Fig 30: Chart D-2 Flow Chart ("G" Sensor Circuit)

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Fig 31: Chart D-3 Schematic

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Fig 32: Chart D-3 Flow Chart (Left Front Wheel Speed Sensor Output)

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Fig 33: Chart D-3 Flow Chart (Right Front Wheel Speed Sensor Output)

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Fig 34: Chart D-3 Flow Chart (Left Rear Wheel Speed Sensor Output)

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Fig 35: Chart D-3 Flow Chart (Right Rear Wheel Speed Sensor Output)

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