WARNING: This page is about a different car, the 2018 Hyundai Accent. However, it is still accessible from the selected car via links, so may be relevant.

TEST ECM GROUND CIRCUIT: Measure resistance between ECM and chassis ground using the backside of ECM harness connector as ECM side check point. If the problem is found, repair it.
Specification : Below 1Ω
TEST ECM CONNECTOR: Disconnect the ECM connector and visually check the ground terminals on ECM side and harness side for bent pins or poor contact pressure. If the problem is found, repair it.
If problem is not found in Step 1 and 2, the ECM could be faulty. If so, make sure there were no DTCs before swapping the ECM with a new one, and then check the vehicle again. If DTCs were found, examine this first before swapping ECM.
RE-TEST THE ORIGINAL ECM: Install the original ECM (may be broken) into a known-good vehicle and check the vehicle. If the problem occurs again, replace the original ECM with a new one. If problem does not occur, this is intermittent problem.
(Refer to "Intermittent Problem Inspection Procedure" in Basic Inspection Procedure (GENERAL SERVICE INFORMATION )

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

ECM Problem Inspection Procedure

Use the Manual With the Right Hardware

When to See a Mechanic