WenmarOpen by Wenmar Pro

Service bulletin 20-FL-007H

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id10178170
Published by NHTSA2020-08-07
Manufacturer's number20-FL-007H
Manufacturer's date2020-07-13
NHTSA componentENGINE AND ENGINE COOLING; EQUIPMENT ADAPTIVE/MOBILITY; ELECTRICAL SYSTEM:SOFTWARE

NHTSA's summary

This bulletin provides information related to an ECM (Engine Control Module) software update for DTC P0128: Coolant Thermostat (Coolant Temp below Thermostat Regulating Temperature) logic revision. There are no drivability symptoms associated with DTC P0128.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Electrical system, Engine, Equipment and accessories, Software

Trouble codes named

P0128

Vehicles listed
HYUNDAI ELANTRA2019, 2020

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Other bulletins for the same vehicles and component
22-01-043H2022-06-10. Service bulletin. Hyundai is conducting a service campaign to enhance the knock sensor logic with the Cylinder Noise Diagnostic System (CNDS) software update. CNDS is to detect abnormal cylinder wall scuffing or noise of the engine block before potentially severe engine damage occurs. If abnormal noise is detected, the Malfunction Indicator Lamp (MIL) will blink continuously. In addition, DTC P1327 will be recorded in the ECM.
Campaign T3W Dea2020-03-07. Service bulletin. Hyundai is conducting a Service Campaign related to an Electronic Control Module (ECM) software update to include cylinder imbalance learning logic optimization for Malfunction Indicator Light illumination.
20-01-008H2020-03-07. Service bulletin. This bulletin provides information related to the Engine Control Module (ECM) software update for 2018 - 2019MY Elantra (AD/ADA) vehicles equipped with 2.0L engine. This software update includes cylinder imbalance learning logic optimization for Malfunction Indicator Light illumination with DTC P0300/P0301/P0302/P0303/P0304 (Cylinder “X” – misfire detected).