Frequently Asked Questions

How much does a check engine light diagnostic cost for a 2025 Toyota Mirai?

• Diagnostic fees typically range from $90–$150 depending on the complexity and testing required.
• At Nalley Toyota Union City, diagnostics are performed by factory-trained technicians using Toyota-approved tools to find the precise cause faster, often saving you money on unnecessary repairs.
• Immediate and long-term savings come from accurate diagnosis, OEM parts, and maintenance that prevents repeat failures.
• Repairs covered under warranty must be completed at a certified dealership to preserve coverage — we handle warranty work promptly and correctly.
• Check our service specials for current offers and easy online scheduling at /specials/service.htm or visit our service center at Nalley Toyota Union City.

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

• Confirm dashboard indicators and listen for unusual noises; safety issues should be addressed first by stopping in a safe place.
• Inspect visible items: secure hatch/doors and verify there are no obvious leaks or warning messages related to the hydrogen system or traction battery.
• A quick visual step is to check for any obvious damage or recent service that could trigger a code; avoid resetting the light yourself.
• Bring the 2025 Toyota Mirai to our service team — certified diagnostics protect warranty coverage and reduce long-term costs by addressing root causes.
• We recommend scheduling online for a prompt check so our factory-trained technicians can evaluate the vehicle accurately.

What does it mean when the check engine light comes on in a 2025 Toyota Mirai?

• The light indicates the onboard diagnostics detected a fault in emissions, fuel cell systems, battery/inverter, or related sensors.
• Issues can range from minor sensor faults to more serious hydrogen system or hybrid component concerns that affect performance or safety.
• Early diagnosis prevents escalation: timely service reduces repair costs and preserves the vehicle’s efficiency and resale value.
• Warranty repairs must be completed at a certified dealership; we provide factory-level diagnostics, OEM parts, and documented service to protect your coverage.
• For peace of mind and accurate repair, bring your Mirai to Nalley Toyota Union City for a professional inspection and repair plan.

What is the most common reason for check engine light on a 2025 Toyota Mirai?

• Common triggers include sensor malfunctions (pressure, voltage, or temperature sensors), battery/inverter issues, or control module messages.
• Because the Mirai is a fuel-cell vehicle, specific hydrogen system or fuel cell stack sensor codes are more common than traditional gasoline-system causes.
• Left unchecked, sensor faults can lead to reduced range, drivability problems, or more costly repairs over time.
• Our dealership often costs less than independent shops overall because accurate diagnostics and factory parts limit repeat visits and long-term expense.
• Remember: warranty-covered repairs must be done at a certified dealership to remain valid — bring your vehicle to Nalley Toyota Union City for proper care.

How long does a check engine light service take?

• Initial diagnostics usually take 30–90 minutes depending on code complexity and onboard testing requirements.
• Simple repairs can often be completed the same day; more involved repairs or parts orders may require additional time or an appointment.
• Nalley Toyota Union City provides efficient service with factory-trained technicians and Toyota-approved equipment to shorten diagnosis and repair cycles.
• Using our dealership often saves you time and money over the long run by ensuring repairs are done right the first time and preserving warranty coverage.
• Schedule service online or contact our service team to get an accurate time estimate based on your Mirai’s symptoms and diagnostic results.