What does this code mean?
The wording below belongs to the named make and communication. Match the complete code, reporting module, model year and engine before applying it.
A code identifies a detected condition, not a part that must automatically be replaced.
Manufacturer wording
Source wording can vary by vehicle and suffix. It is shown as written, not as a universal diagnosis.
P218100Cooling System PerformanceManufacturer communications
3Original wording in English
HYUNDAI
Reported code forms P218100
Some Elantra (CN7) vehicles equipped with the 2.0L AKS NU PE engine may exhibit an illuminated Check Engine light for diagnostic trouble code (DTC) P218100 or P013300 which are related to the Integrated Thermal…
HYUNDAI
Reported code forms P218100
Some Elantra (CN7, CN7A), Kona (OS, SX2), and Sonata Hybrid (DN8 HEV) vehicles equipped with 2.0L engines may illuminate a warning lamp for DTC P218100 (Cooling System Performance) related to the Integrated…
HYUNDAI
Reported code forms P2181
This bulletin provides a procedure for replacing the thermostat on certain 2019 Elantra vehicles. The thermostat may not function properly and may result in Diagnostic Trouble Codes P0128 or P2181. To correct this…
Check vehicle applicability
6A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
Before replacing a part
Record codes and freeze-frame data. Check battery condition, related codes and visible wiring or hose damage. Follow the vehicle's diagnostic procedure and test results before replacing parts.
Can I keep driving?
A code alone cannot establish whether driving is safe. A flashing malfunction light, severe shaking, overheating, oil-pressure warning or loss of braking or steering needs prompt attention. Stop in a safe place and seek assistance when control or engine safety is affected. Follow the vehicle handbook.