---
id: department-0009
title: "How does Castle CDJR of Chesterton diagnose check-engine lights and other issues?"
category: department
subtopic: service-diagnostics
page_type: department
source_url: "https://www.castlecdjrchesterton.com"
tags: ["service", "diagnostics", "check-engine", "troubleshooting"]
questions:
  - "What does a check-engine light mean?"
  - "How do I diagnose a car problem?"
  - "Can Castle CDJR figure out what's wrong with my car?"
related: [service-maintenance-overview, service-recalls, service-scheduling]
dealer: Castle CDJR of Chesterton
---

A check-engine light (or any warning) means your vehicle's computer detected something. It could be minor (loose gas cap) or serious (emission sensor, catalytic converter). Don't ignore it-early diagnosis saves money and prevents bigger problems.

Our Service Department uses advanced diagnostic equipment to read your vehicle's codes, identify the real issue, and recommend the right fix. We explain what's happening in plain language so you can make an informed decision.

**Got a warning light?** **Call (219) 250-9487** to book a diagnostic appointment. Knowing what's wrong is the first step to getting it fixed quickly and fairly.