Service bulletin SC373_TSB

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)
Type	Service bulletin
NHTSA id	11036626
Published by NHTSA	2026-09-02
Manufacturer's number	SC373_TSB
Manufacturer's date	2026-08-21
Campaign id or software version	SC373
NHTSA component	VISIBILITY/WIPER; ENGINE

NHTSA's summary

TECHNICAL SERVICE BULLETIN: VOLUNTARY SERVICE CAMPAIGN: 3-WAY COOLANT VALVE REPLACEMENT (SC373) - This bulletin provides information to replace the 3-way coolant valve. In addition, inspect the 3-way coolant valve harness connector for corrosion, and if necessary, replace the harness connector on certain 2024-2026MY EV6 (CV, CVa) vehicles produced from August 07, 2023 through June 18, 2026. The 3-way coolant valve in the subject vehicles may become damaged and result in a coolant leak. As a result, corrosion may also be present in the 3-way coolant valve harness connector. An inoperative 3-way coolant valve or corrosion within the harness connector may result in reduced Heating, Ventilation, and Air Conditioning (HVAC) performance and/or in the illumination of the “Check electric vehicle system” or “Refill Coolant” warning messages in the instrument cluster.

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

Engine, Glass, wipers and mirrors, Wipers and washers

Vehicles listed
KIA EV6	2024, 2025, 2026

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
SC373B_OWNR	2026-09-30. Service campaign. VOLUNTARY SERVICE CAMPAIGN: OWNER NOTIFICATION (SC373B) - This document is the owner notification advising that Kia is conducting a Voluntary Service Campaign on certain 2024-2026 MY EV6 vehicles to replace the 3-way coolant valve assembly with a new one. In addition, dealers will inspect the 3-way coolant valve harness connector for corrosion and, if necessary, replace the harness connector.
SC373_TSB_R2	2026-09-30. Service bulletin. TECHNICAL SERVICE BULLETIN: VOLUNTARY SERVICE CAMPAIGN: 3-WAY COOLANT VALVE REPLACEMENT (SC373 Revision 2) - This bulletin has been revised to include additional information. New/revised sections of this bulletin are indicated by a black bar in the margin area. This bulletin provides information to replace the 3-way coolant valve. In addition, inspect the 3-way coolant valve harness connector for corrosion, and if necessary, replace the harness connector on certain 2024-2026MY EV6 (CV, CVa) vehicles produced from August 07, 2023 through June 18, 2026. The 3-way coolant valve in the subject vehicles may become damaged and result in a coolant leak. As a result, corrosion may also be present in the 3-way coolant valve harness connector. An inoperative 3-way coolant valve or corrosion within the harness connector may result in reduced Heating, Ventilation, and Air Conditioning (HVAC) performance and/or in the illumination of the “Check electric vehicle system” or “Refill Coolant” warning messages in the instrument cluster.
SC373_TSB_R1	2026-09-30. Service bulletin. TECHNICAL SERVICE BULLETIN: VOLUNTARY SERVICE CAMPAIGN: 3-WAY COOLANT VALVE REPLACEMENT (SC373 Revision 1) - This bulletin has been revised to include additional information. New/revised sections of this bulletin are indicated by a black bar in the margin area. This bulletin provides information to replace the 3-way coolant valve. In addition, inspect the 3-way coolant valve harness connector for corrosion, and if necessary, replace the harness connector on certain 2024-2026MY EV6 (CV, CVa) vehicles produced from August 07, 2023 through June 18, 2026. The 3-way coolant valve in the subject vehicles may become damaged and result in a coolant leak. As a result, corrosion may also be present in the 3-way coolant valve harness connector. An inoperative 3-way coolant valve or corrosion within the harness connector may result in reduced Heating, Ventilation, and Air Conditioning (HVAC) performance and/or in the illumination of the “Check electric vehicle system” or “Refill Coolant” warning messages in the instrument cluster.
TSB_CLI049_R2	2026-09-02. Service bulletin. TECHNICAL SERVICE BULLETIN: PARTIAL REPAIR – ELECTRICAL A/C COMPRESSOR - This bulletin has been revised to include additional information. New/revised sections of this bulletin are indicated by a black bar in the margin area. This bulletin provides information regarding the partial repair of the Air Conditioning (A/C) compressor assembly on some 2011MY~ Optima Hybrid (TF HEV, JF HEV/PHEV), 2015MY~ Soul EV (PS EV), 2017MY~ Niro (DE HEV/PHEV/EV), 2022MY~ EV6 (CV), 2021MY~ Sorento (MQ4 HEV/PHEV), 2023MY~ Sportage (NQ5 HEV/PHEV), and 2023MY~ Niro (SG2 EV/HEV/PHEV) vehicles.
SC373A_OWNR	2026-09-02. Service campaign. VOLUNTARY SERVICE CAMPAIGN: OWNER NOTIFICATION (SC373A) - This document is the owner notification advising that Kia is conducting a Voluntary Service Campaign on certain 2024-2026 MY EV6 vehicles to replace the 3-way coolant valve assembly with a new one. In addition, dealers will inspect the 3-way coolant valve harness connector for corrosion and, if necessary, replace the harness connector.
SC373_QA	2026-08-21. Service campaign. VOLUNTARY SERVICE CAMPAIGN: QUESTION AND ANSWER (SC373) - This document is the Question and Answer Guide containing the most frequently asked questions regarding the Voluntary Service Campaign SC373.
SC373_DPSM	2026-08-21. Service campaign. VOLUNTARY SERVICE CAMPAIGN:DEALER PARTS AND SERVICE MANAGER MEMO (SC373) - This document is the announcement to the dealer Parts and Service managers advising that Kia is conducting a Voluntary Service Campaign on certain 2024-2026 MY EV6 vehicles, manufactured from August 7, 2023 through June 18, 2026, to replace the 3-way coolant valve assembly with a new one. In addition, dealers will inspect the 3-way coolant valve harness connector for corrosion and, if necessary, replace the harness connector.
SC373_DP	2026-08-21. Service campaign. VOLUNTARY SERVICE CAMPAIGN: DEALER PRINCIPAL MEMO (SC373) - This document is the announcement to the dealer principals advising that Kia is conducting a Voluntary Service Campaign on certain 2024-2026 MY EV6 vehicles, manufactured from August 7, 2023 through June 18, 2026, to replace the 3-way coolant valve assembly with a new one. In addition, dealers will inspect the 3-way coolant valve harness connector for corrosion and, if necessary, replace the harness connector.