Service bulletin PS593

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	10159238
Published by NHTSA	2019-04-30
Manufacturer's number	PS593
Manufacturer's date	2019-04-24
NHTSA component	ENGINE AND ENGINE COOLING; ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL

NHTSA's summary

PITSTOP: MIL ON WITH DTC U029F00 - Some 2017-2019MY Niro (DE HEV) vehicles may have a malfunction indicator lamp (MIL) illumination with DTC U029F00 (Lost Communication with Evaporative Emission System Leak Detection Control Module ) active. Prior to following the standard diagnostic steps for the DTC as outlined in KGIS, on vehicles built before October 2018, the NVLD signal wire needs to be checked for insulation and/or core damage.

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, Exhaust and emissions

Trouble codes named

U029F

Vehicles listed
KIA NIRO	2017, 2018, 2019

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

Recalls for the same vehicles and component
2018218	2018-05-01. Engine

A recall listed here may apply to some of the same vehicles. Only the manufacturer can say whether it applies to one vehicle.

Other bulletins for the same vehicles and component
TSB_ENG222_R8	2025-04-18. Service bulletin. TECHNICAL SERVICE BULLETIN: EXCESSIVE OIL CONSUMPTION NU/GAMMA/THETA/KAPPA ENGINES - 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 on diagnosing and/or repairing some 2011-2024MY vehicles (refer to the table on pages 9 and 10 for applicable models and engine), which may exhibit a symptom of excessive oil consumption.
TSB_ENG222_R7	2025-03-04. Service bulletin. TECHNICAL SERVICE BULLETIN: EXCESSIVE OIL CONSUMPTION NU/GAMMA/THETA/KAPPA ENGINES - 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 on diagnosing and/or repairing some 2011-2024MY vehicles (refer to the tables on pages 8-9 for applicable models and engine), which may exhibit a symptom of excessive oil consumption.
TSB_ELE270_R2	2023-11-03. Service bulletin. TECHNICAL SERVICE BULLETIN: SERVICE ACTION: INVERTER COOLANT/DEBRIS FLUSHING/REPLACEMENT FOR CLUSTER MESSAGE "REFILL INVERTER COOLANT" (SA512) - 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 flush out the inverter low-conductivity coolant (BSC-1) on certain 2019-2022MY Niro EV (DE EV) vehicles produced from May 10, 2019 through October 4, 2021, which may exhibit a "Refill inverter coolant" message displayed on the instrument cluster due to poor flow of coolant/antifreeze inside the coolant pipes. In most cases, the inverter reservoir tank coolant may be filled to normal level and no DTC's are stored due to an increase operation of the electric water pump (EWP) that is 2,450 RPMs or more when checked.
TSB_ELE270_R1	2023-07-01. Service bulletin. TECHNICAL SERVICE BULLETIN: SERVICE ACTION: INVERTER COOLANT/DEBRIS FLUSHING/REPLACEMENT FOR CLUSTER MESSAGE 'REFILL INVERTER COOLANT' (SA512) - 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 flush out the inverter low-conductivity coolant (BSC-1) on certain 2019-2022MY Niro EV (DE EV) vehicles produced from May 10, 2019 through October 4, 2021, which may exhibit a 'Refill inverter coolant' message displayed on the instrument cluster due to poor flow of coolant/antifreeze inside the coolant pipes. In most cases, the inverter reservoir tank coolant may be filled to normal level and no DTC's are stored due to an increase operation of the electric water pump (EWP) that is 2,450 RPMs or more when checked.
TSB_ELE270	2023-05-04. Service bulletin. TECHNICAL SERVICE BULLETIN: SERVICE ACTION: INVERTER COOLANT/DEBRIS FLUSHING/REPLACEMENT FOR CLUSTER MESSAGE "REFILL INVERTER COOLANT" (SA512) - This bulletin provides information to flush out the inverter low-conductivity coolant on certain 2019-2022MY Niro EV (DE EV) vehicles produced from May 10, 2019 through October 4, 2021, which may exhibit a "Refill inverter coolant" message displayed on the instrument cluster due to poor flow of coolant/antifreeze inside the coolant pipes. In most cases, the inverter reservoir tank coolant may be filled to normal level and no DTC's are stored due to an increase operation of the electric water pump (EWP) that is 2,450 RPMs or more when checked.
TSB_ENG219_R1	2022-09-30. Service bulletin. TECHNICAL SERVICE BULLETIN: MAINTENANCE REMINDER FEATURE - 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 on setting the "Service Interval Reminder" feature available on most 2014-2023MY Kia vehicles (refer to model list on page 2). If the service interval reminder is set, the customer will be informed to have the next maintenance service performed, which can positively affect vehicle longevity and performance. Refer to TSB ENG241 for 2023MY~ vehicles equipped with the Oil Life Management System (OLMS) feature not included in table on page 2.
PS730	2022-06-03. Service bulletin. PITSTOP: RANDOM MISFIRES/OVERHEATING DUE TO LOW COOLANT - This Pitstop provides information to help identify one cause of low coolant, random misfires, and/or possible overheating on some 2017-2022MY Niro HEV (DE HEV) and 2018-2022MY Niro PHEV (DE PHEV) vehicles. The cause may be a small coolant leak in the EGR Cooler. Locating this leak may be difficult.
TSB_ENG222_R6	2022-03-31. Service bulletin. TECHNICAL SERVICE BULLETIN: EXCESSIVE OIL CONSUMPTION NU/GAMMA/THETA/KAPPA ENGINES - 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 on diagnosing and/or repairing some 2011-2021MY vehicles (refer to the tables on pages 8-9 for applicable models and engine), which may exhibit a symptom of excessive oil consumption.
TSB_ENG222_R5	2022-01-20. Service bulletin. TECHNICAL SERVICE BULLETIN: EXCESSIVE OIL CONSUMPTION NU/GAMMA/THETA/KAPPA ENGINES - 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 on diagnosing and/or repairing some 2011-2021MY vehicles (refer to the tables on pages 8-9 for applicable models and engine), which may exhibit a symptom of excessive oil consumption.
TSB_ENG222_R4	2021-12-23. Service bulletin. TECHNICAL SERVICE BULLETIN: EXCESSIVE OIL CONSUMPTION NU/GAMMA/THETA/KAPPA ENGINES - 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 on diagnosing and/or repairing some 2011-2021MY vehicles (refer to the tables on pages 8-9 for applicable models and engine), which may exhibit a symptom of excessive oil consumption.