A check engine light is your vehicle's way of asking for help — but the code stored in the computer is only the starting point, not the complete answer. At Hahn Automotive in Santa Rosa, our ASE-certified technicians go beyond simply reading codes. We perform thorough diagnostic procedures to identify the true root cause of any engine issue.
We use professional-grade scan tools and our decades of experience to translate diagnostic codes into accurate, cost-effective repair plans. Whether your check engine light is steady or flashing, your vehicle is running rough, or you're failing a smog test, we have the expertise to find the problem.
Many shops will read a code and immediately recommend replacing the part the code points to. We verify the diagnosis before recommending any repair — saving you money and ensuring the real problem is addressed.
Signs You Need Engine Diagnostics
Our Process
Code Retrieval
We connect professional scan tools to retrieve all stored and pending fault codes from your vehicle's computer.
Verified Diagnosis
We go beyond the codes — performing live data analysis, component testing, and visual inspection to find the actual cause.
Clear Explanation
We explain our findings in plain language, provide a written estimate, and answer any questions before work begins.
Repair & Retest
After completing the repair, we clear codes, perform a drive cycle, and confirm the issue is fully resolved before returning your vehicle.
Why Choose Hahn Automotive?
Professional Equipment
We use professional-grade OBD-II scanners and live data tools — not the $40 reader from the auto parts store.
Root Cause Analysis
We find the real problem, not just the symptom. This saves you money on unnecessary parts replacements.
Smog Expertise
If you've failed a smog test, we have the diagnostic expertise to identify and repair the specific issue causing the failure.
Honest Reporting
You receive a written diagnosis with clear explanations. We'll tell you what's urgent and what can wait.