---
id: faq-0066
title: "What should I do if my check engine light comes on?"
category: faq
subtopic: service-and-maintenance
page_type: faq
source_url: "https://www.castlecadillacmchenry.com"
tags: ["warning-lights", "diagnostics", "service"]
questions:
  - "Why is my check engine light on?"
  - "Is it safe to drive with the check engine light illuminated?"
  - "How do I diagnose a check engine code?"
related: [diagnostic-service, vehicle-health]
dealer: Castle Cadillac McHenry
---

A check engine light means your vehicle's onboard diagnostic system has detected an issue-it could be minor (a loose gas cap) or more significant (an emissions system fault). While you can often continue driving, it's wise to have it diagnosed promptly to prevent further damage.

Our Service Department uses advanced diagnostic equipment to read your vehicle's fault codes and identify the exact problem. This lets us fix only what needs fixing, saving you time and money.

Don't ignore the light-bring your Cadillac in as soon as convenient. Call (779) 265-4427 to schedule a diagnostic appointment. We'll get you answers and get you back on the road with confidence.