Consult your service manual for a chart of specific values and pinouts to check against, which should help you narrow down the problem to a specific wire or sensor. This chart is typical.

Antilock Quick Test Check Sheet Using Rotunda 60-pin EEC-IV Breakout Box 0 14-00322 or equivalent
Item To Be Tested Ignition Mode Measure Between Pins Tester Scale/Range Specification Pinpoint Test
Power Feed
Battery Check off batt. Terminals volts 10 minimum
ABS ECU Power on 14 + 1 volts 10 minimum DTC B 1318
Pump Motor Power off 2 + 1 volts 10 minimum DTC C 1095
Valve Power off 13 + 1 volts 10 minimum DTC C 1266
Sensor Resistance
LF Sensor Resistance off 15 + 16 K ohms 1.28-1.92 K ohms A
RF Sensor Resistance off 20 + 7 K ohms 1.28-1.92 K ohms B
LR Sensor Resistance off 17 + 18 K ohms 1.28-1.92 K ohms C
RR Sensor Resistance off 4 + 19 K ohms 1.28-1.92 K ohms D
Sensor Continuity to Ground
LF to Ground off 15 + 1 continuity no continuity A
RF to Ground off 20 + 1 continuity no continuity B
LR to Ground off 17 + 1 continuity no continuity C
RR to Ground off 4 + 1 continuity no continuity D
Sensor Output Voltage
Rotate Wheels at One Revolution Per Second
LF Sensor Output off 15 + 16 AC mV > 100 mV A
RF Sensor Output off 20 + 7 AC mV > 100 mV B
LR Sensor Output off 17 + 18 AC mV > 100 mV C
RR Sensor Output off 4 + 19 AC mV > 100 mV D
ABS Warning Lamp Check on 22 + 1 volts 10V minimum E
Stoplamp Switch Check
Brake Pedal Applied off 9 + 1 volts 10 minimum
Brake Pedal Released off 9 + 1 continuity no continuity

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