Restore Stable Battery Voltage and Electrical Grounding

Safety Precautions: Ensure the engine is off and the key is removed from the ignition before performing electrical work. Wear safety glasses and gloves to protect against battery acid and terminal corrosion.

Required Tools: Multimeter, wire brush or terminal cleaning tool, socket set/wrench, and dielectric grease (optional).

1. Inspect the battery terminals for white or blue-green corrosion. Use a wire brush to clean the terminals and cable clamps until the metal is bright and free of debris.
2. Locate the main engine-to-body ground straps. Remove the mounting bolts, clean the contact surfaces on both the chassis and the engine block with a wire brush to ensure bare metal contact, and securely re-tighten the bolts.
3. Check the battery's state of charge. If the battery is aged or fails a load test, replace it with a new unit that meets the manufacturer's Cold Cranking Amps (CCA) specifications.
4. After reassembly, use a multimeter to measure the battery voltage during engine cranking. Ensure the voltage remains above 10.5V during the start cycle to prevent the EPS module from triggering a low-voltage protection lockout.
5. Verify the fix by starting the engine and observing the EPS warning light on the dashboard; it should extinguish shortly after the engine begins running.

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