NHTSA ID Number: 11028667
Manufacturer Communication Number: 26-EM-004H TSB
TSB/Document Date: 2026-02-10
Summary
Some Tucson (NX4, NX4A) vehicles may have DTC P218100, P2181F0, and/or P2181F1 (Cooling System Performance) set in the Electronic Control Unit (ECU), resulting in an illuminated Check Engine warning lamp. This TSB provides instructions to replace the Integrated Thermal Management (ITM) module and update both the Engine Control Module (ECM) and Transmission Control Module (TCM), if applicable. Follow the flowchart in this bulletin to update the appropriate modules.
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TSB/Document ID: 26-EM-004H TSB
Replacement Service Bulletin Number:
MFR Communication Date: 2026-02-05
MFR Internal Campaign ID/Software Version:
Communication Type: Service Bulletin/Repair Instructions
NHTSA Components: ENGINE
MFR Component System:
MFR Component Subsystem:
Previous TSB | Next TSB |
GROUP
NUMBER
ENGINE
MECHANICAL
DATE
Technical Service Bulletin
SUBJECT:
26-EM-004H
MODEL(S)
FEBRUARY 2026
TUCSON
(NX4, NX4A)
INTEGRATED THERMAL MANAGEMENT (ITM) REPLACEMENT &
ECM/TCU SOFTWARE UPDATE – DTC P218100, P2181F0, P2181F1
IMPORTANT
This field action requires justification in the form of a customer concern, and a confirmed case for
the related symptom outlined in the TSB, prior to any repair work. If justification requirements are
not met, any submitted claims are subject to debit. 8 / 80,000 Emissions Warranty applies.
See Warranty Information section for more details.
Description: Some Tucson (NX4, NX4A) vehicles may have DTC P218100, P2181F0, and/or P2181F1
(Cooling System Performance) set in the Electronic Control Unit (ECU), resulting in an illuminated
Check Engine warning lamp. This TSB provides instructions to replace the Integrated Thermal
Management (ITM) module and update both the Engine Control Module (ECM) and Transmission
Control Module (TCM), if applicable. Follow the flowchart in this bulletin to update the appropriate
modules.
Applicable Vehicles:
Model Year
2022 – 2023
Model
Tucson (NX4)
Tucson (NX4A)
Engine
2.5L GDI
Production Dates
VINs Start with
01/23/2021 - 06/24/2023
KM8
02/03/2021 - 11/21/2023
5NM
Parts Information:
Model
Tucson
(NX4, NX4A)
Part Name
Part Number
Figure
Quantity
Control Assy –
Coolant
Temperature
25600-2S650QQH
1
25462-2S000
1
Pink Antifreeze/
Coolant
00232-19098
2 gal
NOTE: Do NOT use 100% full strength antifreeze. Prepare coolant mixed with distilled/filtered water
to refill the cooling system (35-50% antifreeze, diluted with distilled/filtered water).
Circulate To: General Manager, Service Manager, Parts Manager, Warranty Manager, Service
Advisors, Technicians, Body Shop Manager, Fleet Repair
INTEGRATED THERMAL MANAGEMENT (ITM) REPLACEMENT &
ECM/TCU SOFTWARE UPDATE – DTC P218100, P2181F0, P2181F1
SUBJECT:
SST Information:
Tool Name
Tool Number
VCI 3
Figure
Ordering Information
Website:
https://hyundaiessentialtools.com/
G0VHNNN06
Email:
Hyundaitools@snapon.com
VCI 2
Phone: 1-855-763-9199
Hours: 7 AM – 7 PM CST
G1XDDMN001
NOTE: VCI 2 can NO longer be ordered but can be used for the updates in this TSB.
GDS Information:
Model
MY
System
Event
Number*
Description
Tucson
(NX4, NX4A)
2022-2023
1281
NX4/NX4A ECU DTC P2181 Improvement
Tucson with
ISG (NX4)
2022
1032
NX4 Theta III 2.5GDI TCU S/W Improvement for
ISG Logic Improvement
(2022MY ONLY – TCU for VINs starting w/ “KMH”)
1034
NX4A Theta III 2.5GDI TCU S/W Improvement for
ISG Logic Improvement
(2022MY ONLY – TCU for VINs starting w/ “5NM”)
AT
Tucson with
ISG (NX4A)
2022
(*or use a later available event listed in the GDS Engine or AT Update screen if one is available.)
TSB #: 26-EM-004H
Page 2 of 18
INTEGRATED THERMAL MANAGEMENT (ITM) REPLACEMENT &
ECM/TCU SOFTWARE UPDATE – DTC P218100, P2181F0, P2181F1
SUBJECT:
Warranty Information:
Model
Tucson
(NX4)
Op. Code
Operation
Op.
Time
Causal Part
50D137R0
DTC Check, GDI ITM
Replacement & ECM Update
2.0
M/H
39110-2S105
DTC Check, GDI ITM
Replacement + ECM Update
50D137R1
& TCU Update
(ISG Option & Certain 22MY)
2.2
M/H
39110-2S105
DTC Check, GDI ITM
50D137R4
Replacement & ECM Update
2.0
M/H
Nature
Code
Cause
Code
L31
ZZ4
39110-2S161
Tucson
(NX4A)
DTC Check, GDI ITM
Replacement, ECM Update & 2.2
50D137R5
39110-2S161
TCU Update
M/H
(ISG Option & Certain 22MY)
NOTE 1: Submit claim on Claim Entry Screen as "Campaign" type.
NOTE 2: 8 / 80,000 Emissions Warranty applies to the part(s) and repair procedure(s) outlined in this
TSB. Prior to beginning any repair work, ensure the part(s) associated with the repair procedure are
within Emissions Warranty, observing mileage and Warranty Start Date or date of first use. If the
subject part(s) are out of warranty coverage, the dealer has the option to submit a PA Request for
goodwill consideration on a case-by-case basis.
NOTE 3: If any part(s) not subject to this TSB are found in need of replacement while performing the
repair procedure, and the affected part(s) are still under warranty, the dealer may submit a separate
claim using the same repair order. If the part(s) not subject to this TSB are out of warranty coverage,
the dealer has the option to submit a PA Request for goodwill consideration on a case-by-case basis.
NOTE 4: This TSB includes repair justification in the form of automatically uploaded DTC(s) via GDS
e-Report at the time of diagnosis. To ensure adherence to the Digital Documentation Policy before
claim submission, DTC history can be reviewed via the e-Report function within the GDS.
Additionally, required photos include a capture of the ECU Update “Success" screen for the
associated update event.
NOTE 5: The incident parts are subject to callback through the normal Warranty Technical Center
(WTC) parts return process. Claim is subject to debit if the part is not returned.
NOTE 6: Engine Control Module (ECM) software update is required in all applications. The
Transmission Control Module (TCM) software update is only required for the 2.5L GDI vehicles
equipped with ISG.
TSB #: 26-EM-004H
Page 3 of 18
SUBJECT:
INTEGRATED THERMAL MANAGEMENT (ITM) REPLACEMENT &
ECM/TCU SOFTWARE UPDATE – DTC P218100, P2181F0, P2181F1
Service Procedure:
DIGITAL DOCUMENTATION
This TSB includes repair justification in the form of automatically uploaded DTC(s) via GDS eReport at the time of diagnosis. To ensure adherence to the Digital Documentation Policy
before claim submission, DTC history can be reviewed via the e-Report function within the
GDS. Additionally, required photos include a capture of the ECU Update “Success" screen for
the associated update events.
NOTICE
Applying the recommended torque to all fasteners is essential to reduce potential issues from
occurring after the service procedure.
NOTICE
For proper engine operation, ITM replacement MUST be completed before the ECU update.
i
Information
This TSB ONLY applies if GDS fault code searching results identify DTCs P218100, P2181F0,
and/or P2181F1.
Table of Contents
•
Flowchart.................................................................................................................................. 5
•
DTC Check ............................................................................................................................... 6
•
ITM Replacement ..................................................................................................................... 6
•
Service Procedure .................................................................................................................... 7
•
ECM Update Procedure ........................................................................................................... 9
•
TCU Update Procedure .......................................................................................................... 11
•
ITM Coolant Filling Mode ....................................................................................................... 13
TSB #: 26-EM-004H
Page 4 of 18
SUBJECT:
INTEGRATED THERMAL MANAGEMENT (ITM) REPLACEMENT &
ECM/TCU SOFTWARE UPDATE – DTC P218100, P2181F0, P2181F1
Flowchart
Vehicle In
Follow normal diagnostic
process
No
DTC Check
(P218100, P2181F0,
P2181F1)
Yes
ITM Replacement
Manual ECM Software
Update
(Event # 1281)
Auto TCU
Software Update
(Event # 1032/1034)
Yes
TCU ROM ID
Verification
No
ITM Coolant Filling Mode
Vehicle Out
TSB #: 26-EM-004H
Page 5 of 18
INTEGRATED THERMAL MANAGEMENT (ITM) REPLACEMENT &
ECM/TCU SOFTWARE UPDATE – DTC P218100, P2181F0, P2181F1
SUBJECT:
DTC Check
1.
Use GDS to scan for DTCs P218100,
P2181F0, and/or P2181F1 (Cooling System
Performance):
• If these DTCs are NOT detected, this
TSB does NOT apply. Follow the
normal diagnostic process.
•
If these DTCs are detected, then
proceed to the ITM Replacement
procedure.
ITM Replacement
1.
Replace the ITM (A) by referring to the shop
manual.
•
Engine Mechanical System > Cooling
System > Integrated Thermal
Management Module (ITM) > Repair
procedures
A
2.
Reinstall all parts in the reverse order of the
removal process.
i
Information
The ITM design inverts the connector’s
orientation.
TSB #: 26-EM-004H
Page 6 of 18
SUBJECT:
INTEGRATED THERMAL MANAGEMENT (ITM) REPLACEMENT &
ECM/TCU SOFTWARE UPDATE – DTC P218100, P2181F0, P2181F1
Service Procedure
NOTICE
Initially perform the ECM update in Manual Mode and TCU update in Auto Mode (if applicable).
NOTICE
Ensure the vehicle’s battery charge is above 11.0 Volts and the tablet’s battery charge is
above 30% before performing a software update to avoid update failure.
i
Information
•
Turn OFF all lamps (do NOT leave head lamp switch in auto mode) and all accessories.
•
Perform update with the ignition switch in the ON position.
•
Do NOT disconnect any cables connected to the vehicle or scan tool during the update.
•
Do NOT start the engine during the update.
•
Do NOT turn OFF the ignition switch during the update.
TSB #: 26-EM-004H
Page 7 of 18
SUBJECT:
INTEGRATED THERMAL MANAGEMENT (ITM) REPLACEMENT &
ECM/TCU SOFTWARE UPDATE – DTC P218100, P2181F0, P2181F1
ECM Manual Mode Passwords:
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