This service manual for the 2021 Hyundai Elantra (CN7) is your go-to resource for everything you need to maintain, service, and repair your Elantra with precision. Covering all major systems — engine and fuel systems, transmission, suspension, brakes, electrical and electronic systems, body and interior elements — the manual delivers detailed diagnosis instructions, assembly/disassembly procedures, maintenance schedules and technical specifications. Whether you are doing routine maintenance or deeper system checks, the step-by-step guides and technical data ensure that work is done correctly and safely.
By following the guidelines in the manual, owners and mechanics can preserve the performance, safety, and longevity of the vehicle. Regular maintenance as described — checking fluids, inspection of brake, steering, suspension and emissions systems, tire condition, and electrical components — helps prevent wear and avoid unexpected breakdowns. Proper documentation of services also helps maintain warranty coverage and ensures reliability over time.

The emission control system of your vehicle is covered by a written limited warranty. Please see the warranty information contained in the Owner’s Handbook & Warranty Information booklet in your vehicle.
Description and operation Description The climate control air filter is located in the blower unit. It eliminates foreign materials and odor. The particle filter performs a role as an odor filter as well as a conventional dust filter to ensure comfortable interior environment.
Diagnosis with Diagnostic tool1.In the body electrical system, failure can be quickly diagnosed by using the vehicle diagnostic system (Diagnostic tool).The diagnostic system (Diagnostic tool) provides the following information.(1)Fault Code Searching : Checking failure and code number (DTC)(2)Data Analysis : Checking the system input/output data s