Frequently Asked Questions

How much does a check engine light diagnostic cost for a 2025 Lexus IS 300?

• Diagnostics at Nalley Lexus Roswell typically start with a professional scan and inspection; we often cost less than independent shops while offering factory-trained techs and OEM tools.
• Initial scan fees cover code readout, basic inspection and a written estimate; additional diagnostic time is billed only if needed and explained up front.
• Choosing the dealership offers immediate and long-term savings by preventing misdiagnosed repairs and preserving OEM parts and labor warranties.
• Remember: any repair covered under warranty must be performed at a certified dealership to keep coverage valid.

What does it mean when the check engine light comes on in a 2025 Lexus IS 300?

• The light signals the vehicle’s diagnostic system has detected an emissions, engine, or sensor issue—ranging from a loose fuel cap to a misfire or turbo fault.
• Codes are logged by the onboard computer and point technicians to the subsystem needing attention; a scan at our service center identifies the exact codes.
• Early diagnosis at Nalley Lexus Roswell helps avoid damage to the turbocharger, catalytic converter, or other costly components and maintains fuel economy.
• Warranty-related concerns must be serviced at a certified dealership to ensure proper coverage and documentation.

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

• Begin with the simple checks: secure the gas cap and verify you used premium unleaded fuel, as the 2.0L turbo engine is tuned for premium fuel.
• Next, schedule a prompt scan with our service department so factory-trained technicians can read stored codes and advise required repairs.
• Addressing issues at the dealership delivers immediate savings—accurate diagnostics prevent unnecessary parts replacement and longer-term costs.
• Any warranty-covered repair should be completed at a certified dealership to protect your coverage and ensure OEM procedures.

How long does a check engine light service take?

• Most initial diagnostic scans and inspections are completed within one hour, though some issues require deeper diagnostics and additional time.
• If a simple fix is identified—sensor replacement or tightening the fuel cap—many services can be completed same day at Nalley Lexus Roswell.
• Complex repairs that involve the turbocharger, catalytic converter, or internal engine components will require diagnostic time and parts; we provide clear timelines and written estimates.
• Repairs covered under warranty must be performed at a certified dealership; using our service team protects warranty rights and can reduce long-term repair costs.

What is the most common reason for check engine light on a 2025 Lexus IS 300?

• Common triggers include oxygen sensor faults, misfires, catalytic converter efficiency codes, or turbo underboost warnings on a turbocharged 2.0L engine.
• Many issues start as minor sensor problems; prompt dealer diagnosis prevents these from becoming much larger, costlier failures.
• Nalley Lexus Roswell’s factory-trained technicians use OEM parts to restore correct operation and prevent repeated failures, saving you money over time.
• For warranty-covered concerns, repairs must be completed at a certified dealership to maintain coverage and ensure factory procedures are met.