Frequently Asked Questions

What is the most common reason for check engine light on a 2016 Toyota Mirai?

• Most often the light points to sensor or emissions-system alerts, such as faulty sensors or control module messages affecting drivability.
• In hydrogen fuel cell vehicles like the Mirai, diagnostics can reveal issues with sensors, power electronics, or control systems tied to the fuel cell stack.
• Ignoring early warnings risks greater strain on components and can turn an inexpensive sensor repair into a costly component replacement.
• Bringing the vehicle to Nalley Toyota of Roswell ensures correct diagnosis by factory-trained technicians who limit long-term expense and protect warranty coverage.

What does it mean when the check engine light comes on in a 2016 Toyota Mirai?

• The light indicates the onboard computer detected a fault—ranging from minor sensor irregularities to more serious powertrain or fuel cell system issues.
• It can mean reduced efficiency, emission-control faults, or a condition that could damage components if left unaddressed.
• An illuminated light calls for prompt diagnostics; Nalley Toyota of Roswell quickly identifies severity and recommends repairs to avoid larger costs.
• Warranty-covered repairs must be completed at a certified dealership to preserve coverage and deliver long-term savings.

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

• Check the instrument panel for additional warnings or messages that indicate severity or affected systems.
• If the light is steady, schedule a diagnostic soon; if it is flashing, pull over safely and contact our service department immediately.
• Avoid attempting complex resets yourself—temporary resets can hide underlying faults and lead to repeated failures or safety risks.
• Contact Nalley Toyota of Roswell to arrange a fast inspection by factory-trained technicians who can diagnose with Toyota-approved tools.

How much does a check engine light diagnostic cost for a 2016 Toyota Mirai?

• Diagnostic fees typically range by complexity; expect a straightforward scan fee and a full diagnostic when needed—many initial scans are competitively priced compared with independent shops.
• Nalley Toyota of Roswell often costs less than independent shops while offering a higher level of service from factory-trained technicians and Toyota-approved equipment.
• Immediate accurate diagnostics reduce repeat visits and deliver long-term savings by preventing additional damage or compounded repairs.
• Remember: any repairs covered under warranty must be performed at a certified dealership to maintain coverage and maximize savings.

How long does a check engine light service take?

• Basic diagnostics can take 30–90 minutes depending on code complexity and test requirements; more involved repairs naturally take longer.
• Minor sensor replacements or software updates are often completed the same day; complex fuel cell or drivetrain repairs may require parts and additional time.
• Nalley Toyota of Roswell offers transparent time estimates and scheduling options to minimize downtime and provide efficient, reliable service.
• Warranty-covered repairs must be handled at a certified dealership, ensuring proper procedures and protecting future savings.