2. Perform flush and filter cleaning
circulating coolant for 5 minutes.
(Air ON, Pump ON, Inlet Valve ON)
3. Perform Air Drain for 2 minutes to
discharge and drain the coolant.
(Air ON, Pump OFF, Inlet Valve OFF)

F
E

Coolant
tank
outlet
(hose)

Red outlet hose

0

Coolant tank
inlet (hose)

Blue inlet hose

Coolant
circulation
container

Coolant pump and
air pressurizer

Foreign material filter

TSB #: 23-01-049H

Page 9 of 27
SUBJECT:

SUBJECT:

B9.

COOLING SYSTEM CIRCUIT DEBRIS DISCHARGE
AND COOLANT CHANGE
`
(SERVICE CAMPAIGN T9E)

Disconnect the inlet and outlet hoses of the
cleaning equipment from the vehicle.
Set aside the separated reservoir tank for
cleaning at a later time.

Cleaning of ‘EWP - EPCU - OBC – Motor
Radiator’ cooling circuit section.

i Information
This cooling circuit requires thorough
cleaning in both directions with steps
B10, B12 and then B13 (repeats B10).

B10.

After the vehicle is lifted, connect the hoses
securely to vehicle and operate the
equipment as follows:
EQUIPMENT

VEHICLE CONNECTION POINT

Blue inlet
EWP inlet hose
hose
Red outlet
Radiator outlet nipple
hose
1. Perform flush and filter cleaning
circulating coolant for 5 minutes.
(Air ON, Pump ON, Inlet Valve ON)
2. Perform Air Drain for 2 minutes to
discharge and drain the coolant.
(Air ON, Pump OFF, Inlet Valve OFF)

TSB #: 23-01-049H

Blue inlet hose

Red outlet hose

Page 10 of 27
SUBJECT:

SUBJECT:

COOLING SYSTEM CIRCUIT DEBRIS DISCHARGE AND COOLANT CHANGE
(SERVICE CAMPAIGN T9E)

B10.
cont.
Red outlet hose

Blue inlet hose

Radiator
outlet
(nipple)

EWP inlet
(hose)

EWP

Red outlet hose

0

Blue inlet hose

Coolant
circulation
container

Coolant pump and
air pressurizer

Foreign material filter

TSB #: 23-01-049H

Page 11 of 27
SUBJECT:

SUBJECT:

COOLING SYSTEM CIRCUIT DEBRIS DISCHARGE
AND COOLANT CHANGE
`
(SERVICE CAMPAIGN T9E)

B11. While the cleaning equipment is in operation,
remove the reservoir tank to clean the
residual coolant and debris inside.
Inject water and blow air through the
reservoir tank.

B12. Swap the equipment hoses in the opposite
direction from that of step B10.

Radiator
outlet
(nipple)

To ensure the hoses are securely connected
to the vehicle, follow these instructions:
EQUIPMENT

EWP inlet
(hose)

0

VEHICLE CONNECTION POINT

Blue inlet
Radiator outlet nipple
hose
Red outlet
EWP inlet hose
hose
1. Perform flush and filter cleaning
circulating coolant for 5 minutes.
(Air ON, Pump ON, Inlet Valve ON)
2. Perform Air Drain for 2 minutes to
discharge and drain the coolant.
(Air ON, Pump OFF, Inlet Valve OFF)

Red outlet hose

B13. Swap back the equipment hoses and
perform cleaning then air draining again
(step B10 again).

B14. Remove the hoses of the circulation
equipment and reinstall the existing hoses of
the vehicle.

Circulation
outlet
(nipple)

Blue inlet hose

Coolant
circulation
container

Coolant pump and
air pressurizer

Foreign material filter

Decide next step based on Valve type:
VEHICLE
VALVE
GO TO
PRODUCTION
TYPE
STEP
DATE
Valve type

Before 4/8/20

➔ B15

“T” branch
pipe type

From 4/8/20 or
later

➔ B17

TSB #: 23-01-049H

Page 12 of 27
SUBJECT:

SUBJECT:

COOLING SYSTEM CIRCUIT DEBRIS DISCHARGE AND COOLANT CHANGE
(SERVICE CAMPAIGN T9E)

B15. Cleaning the Valve-Type High Voltage
Battery Cooling Circuit, Including Battery
Chiller, Coolant Heater, and Coolant
While the vehicle is lifted, connect the hoses
securely to vehicle and operate the
equipment as follows:
VEHICLE CONNECTION
EQUIPMENT
POINT
Blue inlet
Battery chiller outlet hose
hose
(see (H) in diagram)
Red outlet
Battery inlet nipple
hose
1. Perform flush and filter cleaning
circulating coolant for 5 minutes.
(Air ON, Pump ON, Inlet Valve ON)
2. Perform Air Drain for 2 minutes to
discharge the coolant.
(Air ON, Pump OFF, Inlet Valve OFF)
Battery
chiller outlet
(hose)

H

0

Battery
inlet
(nipple)

Blue inlet hose
Red outlet hose

Coolant
circulation
container

Coolant pump and
air pressurizer

Foreign material filter

B16. After B15 is complete, skip to B18.
TSB #: 23-01-049H

Page 13 of 27
SUBJECT:

SUBJECT:

COOLING SYSTEM CIRCUIT DEBRIS DISCHARGE
AND COOLANT CHANGE
`
(SERVICE CAMPAIGN T9E)

B17. Cleaning the (T-Branch Pipe Type)
Cooling Circuit Section of the Battery
Chiller, Coolant Heater, and High Voltage
Battery
While the vehicle is lifted, connect the hoses
securely to vehicle and operate the
equipment as follows:
EQUIPMENT

VEHICLE CONNECTION POINT

Blue inlet
Battery chiller outlet hose
hose
(see (H) in diagram)
Red outlet
Battery inlet nipple
hose
1. Perform flush and filter cleaning
circulating coolant for 5 minutes.
(Air ON, Pump ON, Inlet Valve ON)
2. Perform Air Drain for 2 minutes to
discharge the coolant.
(Air ON, Pump OFF, Inlet Valve OFF).
Battery
chiller outlet
(hose)

I
0

Battery
inlet
(nipple)

Blue inlet hose
Red outlet hose
Coolant
circulation
container
Coolant pump and
air pressurizer

Foreign material filter

TSB #: 23-01-049H

Page 14 of 27
SUBJECT:

SUBJECT:

COOLING SYSTEM CIRCUIT DEBRIS DISCHARGE AND COOLANT CHANGE
(SERVICE CAMPAIGN T9E)

B18. Disconnect the hoses from the circulation
equipment of the vehicle and reinstall the
original hoses back to their original positions
on the vehicle.
B19. Reconnect the service interlock connector or
service safety switch that was previously
disconnected from the battery.
B20. Once all hoses in the vehicle are confirmed
to be correctly installed, fill the reservoir tank
with the improved low-conductivity coolant
(BSC-2). Use the GDS-M system to perform
air bleeding for 30 minutes by circulating the
coolant through the EWP.

i Information
•
•

•

Inject coolant into the reservoir tank
based on the optional specifications of
each model (~10 – 13 L).
If the degassing hose of the reservoir
does not have a valve before coolant
injection, restore any flow path
blockage that was previously operated
on in B7. If there is a valve, ensure it is
in the OPEN position (image on the
right).
After flushing a single vehicle, remove
the equipment filter and thoroughly
wash away any foreign substances.

B21. After completing the coolant fill, close the
degas hose valve.

B22. Take a STUI photo of the coolant reservoir
bottle complete filled after the flushing
cleaning and coolant refill.

STUI
Please include the last 6 digits of the
VIN and date of repair on a piece of
paper. Ensure the VIN and date of
repair are clearly visible. Upload the
photo to STUI.

B23. Start the engine and verify if the message
"Coolant supplement" or Inverter Coolant”
warning does not display.

TSB #: 23-01-049H

Page 15 of 27
SUBJECT:

SUBJECT:

COOLING SYSTEM CIRCUIT DEBRIS DISCHARGE
AND COOLANT CHANGE
`
(SERVICE CAMPAIGN T9E)

B24. Use an air gun to clean the filter and filter
case of the equipment, removing any foreign
substances.
1. Blow the filter from the inside to the
outside using the air gun.
2. Pay special attention to spraying air
between the filter gaps to remove
foreign substances effectively, as
there may be a significant buildup in
these areas.
3. Skipping this step may result in
decreased flow rate and reduced
cleaning effectiveness of the
equipment due to foreign substances
being stuck in the filter.

NOTICE
Use an air gun to inject air with precision
into the gaps of the filter's inner wall, as
sludge may be stuck there. Rotate the
filter to ensure even spraying.

TSB #: 23-01-049H

Page 16 of 27
SUBJECT:

SUBJECT:

COOLING SYSTEM CIRCUIT DEBRIS DISCHARGE AND COOLANT CHANGE
(SERVICE CAMPAIGN T9E)

C. Ioniq (AE) EV - Debris Discharge and Coolant Change
C1.

Initial EWP RPM will be checked at vehicle
start in Ready mode:
• If it is above 2,000 RPM, proceed to
step C2.
• If it is above 2,450 RPM, the phrase
“Coolant supplement” or “Inverter
Coolant” warning light may appear on
the cluster.

C2.

Select the Data Analysis (A) icon on the
GDS-M initial screen.

A

C3.

Select the BMS (B) icon and press the ‘OK’
button.

i Information
Example of the Data Analysis Graph at
vehicle start up in Ready mode.
The vehicle has 2 EWP and one of the
EWP briefly increased above 2450 as
seen by the MAX 2460 RPM.

TSB #: 23-01-049H

B

Page 17 of 27
SUBJECT:

SUBJECT:

C4.

COOLING SYSTEM CIRCUIT DEBRIS DISCHARGE
AND COOLANT CHANGE
`
(SERVICE CAMPAIGN T9E)

Scroll down to verify that the Battery BTMS
Valve Control Mode (C) is set to Combined
Mode by:
1. If the mode is set to Separated Mode,
perform ignition on/off or key on/off.
2. Change the mode to Combined Mode