Frequently Asked Questions

How much does a check engine light diagnostic cost for a 2026 Mercedes-Benz GLS?

• Diagnostic fees vary by issue, but our dealership provides transparent pricing and initial scan rates that are often lower than independent shops, while delivering factory-level expertise.
• Performing timely diagnostics can prevent costly long-term repairs—catching issues early saves on parts and labor over time.
• Any repair covered under warranty must be performed at a certified dealership to maintain coverage—our technicians handle warranty work on-site.
• Check current offers and service specials at Service Specials and schedule online at Schedule Service.

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

• Confirm the gas cap is secure—an improperly seated cap is a common trigger for the light and an easy fix.
• Look for obvious signs: low oil or coolant levels, visible leaks, or smoke—these demand immediate attention.
• If the light stays on after basic checks, bring your 2026 Mercedes-Benz GLS to our dealership so factory diagnostics can identify root causes accurately.
• Using our certified service prevents unnecessary parts replacement and protects warranty eligibility; schedule service at Schedule Service.

What does it mean when the check engine light comes on in a 2026 Mercedes-Benz GLS?

• The light signals a fault detected by the engine control system—ranging from minor sensor issues to engine misfires or emissions component failures.
• Severity varies: a steady light often indicates problems to be diagnosed soon; a flashing light usually indicates an urgent condition requiring immediate attention.
• We use OEM-grade scanners to read fault codes, interpret causes, and recommend repairs that protect performance and long-term ownership costs.
• Warranty-covered diagnostics and repairs must be performed at a certified dealership to retain coverage—our technicians will advise you on savings and next steps.

What is the most common reason for check engine light on a 2026 Mercedes-Benz GLS?

• Common triggers include a loose or damaged gas cap, faulty oxygen sensors, or emissions system issues; modern engines also flag misfires and fuel system irregularities.
• Ignoring these warnings can raise fuel use, increase emissions, and lead to more expensive repairs such as catalytic converter replacement.
• Our dealership often delivers lower total ownership costs than many independent shops because we diagnose correctly the first time and use genuine parts.
• For reliable fixes and warranty protection, have any repairs performed at Mercedes-Benz of Lynnfield—see available offers at Service Specials.

How long does a check engine light service take?

• Initial diagnostic scans typically take 30–60 minutes; more complex diagnostics or road testing can extend the appointment to 90 minutes or more.
• Simple fixes, like tightening a gas cap or replacing a sensor, are often completed the same day; larger repairs vary by parts availability and required labor.
• Scheduling ahead at Schedule Service reduces wait time and helps our factory-trained technicians prioritize your 2026 Mercedes-Benz GLS efficiently.
• Choosing our dealership provides immediate and long-term savings through accurate diagnostics, correct repairs, and warranty protection—repairs covered by warranty must be performed at a certified dealership.