Relay is located behind left side of dash. Disconnect relay harness connector and remove relay from holder. Apply battery voltage to relay terminal No. 4 (positive) and ground terminal No. 2 (negative). See Fig 1 .
Using a DVOM, check for continuity between relay terminals No. 1 and 5. Continuity should be present. Check for continuity between relay terminals No. 5 and 3. Continuity should be present. Replace relay if continuity is not present for both checks.
Using DVOM, check voltage between relay harness connector terminals No. 4 and 5 and vehicle ground. If battery voltage is not present on both terminals, inspect and repair appropriate circuit. See appropriate wiring diagram in WIRING DIAGRAMS article.
Ensure ignition is off. Disconnect ECM harness connector. Connect jumper wire between ECM harness connector terminal No. 27 and vehicle ground. See Figure . Using ohmmeter, check resistance between relay harness connector terminal No. 2 and vehicle ground. Continuity should be present. If continuity is not present, inspect and repair circuit as needed.

Fig 1: Checking SFI Control Relay

Courtesy of HYUNDAI MOTOR CO.

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

SFI Control Relay