P0605 on Hyundai Sonata
Internal Control Module Read Only Memory (ROM) Error
Methodology: Reviewed against the SAE J2012 generic DTC definition and NHTSA owner-complaint patterns, then scoped to Hyundai Sonata context without treating complaints as confirmed diagnoses.
Sources: SAE/OBD-II definitions, manufacturer service information, and public reliability reports (including NHTSA where applicable).
- SAE J2012 Diagnostic Trouble Code Definitions — Generic diagnostic trouble code definition reference for P0605.
- NHTSA recalls, complaints, and manufacturer communications — Used to check public owner complaint context, recall status, and safety-related manufacturer communications by VIN or vehicle.
Limits: Guidance is informational and may not match every model-year or revision. Confirm with the official manual and diagnostics before replacing parts. For safety-critical or electrical work, use a qualified technician.
What P0605 Means on Your Hyundai Sonata
P0605 is a diagnostic trouble code indicating: Internal Control Module Read Only Memory (ROM) Error. This code relates to the computer and output circuits system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.
Real Hyundai Sonata Owner Reports
Source: NHTSA Complaints Database
"My husband and i are the owners of two 2011 hyundai sonatas. our complaint is based on the fact that we feel that hyundai has either purposely or in ignorance created an inherent defect in its battery system."
"Reconnecting the battery after servicing the car the vehicle gets a check engine light p0106 code (p0106 manifold absolute pressure/barometric pressure circuit range/performance). the engine runs normal."
"During cold weather, the 2.0 turbo sonata engine will cut power to the car and go into a "limp" mode if an over boost code (usually p0605 & p2110 ), is triggered. this causes an unsafe situation as there is very little power available to get out of the way or can cause a rear vehicle crash."
"Purchased car with just under 97000 miles. Was working terrific. Time for the first oil change and 2 miles after the change the car froze and went limp. Traveling 45 miles per hour it recorded a trouble code on my monitoring device. P0605 - ROM error and the car was dead."
All reports filed by vehicle owners directly with the U.S. Department of Transportation.
📊 Complaint Trend by Model Year
Common Causes on Hyundai Sonata
Based on NHTSA complaint component analysis for this vehicle.
What To Do Next
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1
Check for recalls on YOUR VIN
Go to nhtsa.gov/recalls and enter your VIN. If your vehicle is covered, repairs are free.
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2
Get a proper diagnosis
A code alone doesn't tell you the exact failed part. A diagnostic at a shop ($50–$150) pinpoints the root cause before you spend money on parts.
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3
Compare repair quotes
Get 2–3 quotes. Dealer vs. independent shop prices often differ 30–50% for the same repair.