Frequently Asked Questions

What is the first thing to check when the check engine light comes on?

• Check for obvious issues first: a loose or missing gas cap can trigger the light and is an easy fix.
• Note any changes in performance, sounds, smells, or dashboard warnings to share with our technicians.
• If you smell fuel or experience rough running, stop driving and arrange a tow to avoid further damage.
• Record when the light appeared and any recent service or fuel stops — that helps with diagnosis.
• For warranty-covered concerns, remember repairs must be completed at a certified dealership like Nalley Lexus Smyrna to preserve coverage.

How much does a check engine light diagnostic cost for a 2018 Lexus LC 500h?

• Diagnostic fees vary, but Nalley Lexus Smyrna offers competitive rates and transparent quotes before work begins.
• We often cost less than many independent shops when you consider immediate savings from accurate diagnosis and long-term savings from lasting repairs by factory-trained techs.
• Any repairs covered under warranty must be performed at a certified dealership to remain eligible for coverage.
• Our diagnostics include up-to-date OEM software and genuine parts pricing estimates so you know total cost and savings up front.
• Ask about current service specials and bundled maintenance to maximize short- and long-term value.

What does it mean when the check engine light comes on in a 2018 Lexus LC 500h?

• A check engine light indicates the vehicle’s onboard diagnostics detected an issue — anything from an emissions fault to a serious mechanical problem.
• It can be triggered by emissions sensors, ignition misfires, fuel trim problems, or evaporative system leaks.
• Some causes are minor, but others can lead to reduced fuel economy, higher emissions, or engine damage if ignored.
• Timely diagnostics at Nalley Lexus Smyrna identify the root cause, preventing costly secondary failures and preserving long-term value.
• Warranty repairs must be done at a certified dealership to ensure coverage and proper OEM procedures.

What is the most common reason for check engine light on a 2018 Lexus LC 500h?

• Common causes include oxygen sensor wear, catalytic converter efficiency codes, misfires, and evap system leaks from loose gas caps.
• Oxygen sensors and catalytic issues often start small but can degrade fuel economy and emissions over time.
• Diagnosing early at Nalley Lexus Smyrna reduces repair costs and helps avoid more expensive replacements later.
• Our factory-trained technicians use OEM tools to confirm codes and recommend the most cost-effective, lasting repairs.
• Remember: warranty-covered fixes must be completed at a certified dealership to remain valid.

How long does a check engine light service take?

• Basic diagnostic scans often take 30–60 minutes, depending on symptoms and required road checks.
• If further testing, parts ordering, or extended road diagnostics are needed, total time can extend to several hours or a day.
• At Nalley Lexus Smyrna we provide time estimates up front and prioritize efficient repairs to minimize downtime.
• Choosing our dealership often saves time and money long term because factory-trained techs diagnose correctly the first time.
• For warranty repairs, timely service at a certified dealership preserves coverage and avoids repeat visits later.