Remove ABS control relay. See Figure. Using a DVOM, check continuity at specified terminals. Continuity should exist between terminals No. 9 and 10. Continuity should not exist between terminals No. 7 and 8. See Fig 1. If continuity is not as specified, replace control relay.
Using fused jumper wire, connect positive battery terminal to terminal No. 10. Connect negative battery terminal to terminal No. 9. Continuity should exist between terminals No. 7 and 8. If continuity is not as specified, replace control relay. Disconnect battery from relay.
Continuity should exist between terminals No. 1 and 9. Continuity should not exist between terminals No. 2 and 5. Using ohmmeter capable of testing diodes, check for continuity between terminals No. 4 and 5. Transpose ohmmeter leads. Repeat measurement.
If continuity exists or circuit is open for both measurements, actuator diode is defective. Repair or replace relay, then go to next step. If continuity exists for only one measurement, temporarily substitute known good ABS ECU. Retest system.
Using fused jumper wire, connect positive battery terminal to terminal No. 1. Connect negative battery terminal to terminal No. 9. Continuity should exist between terminals No. 2 and 5. Continuity should not exist between terminals No. 2 and 6. If continuity is not as specified, replace control relay.

Fig 1: Identifying ABS Control Relay Terminals

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

ABS Control Relay