NHTSA ID Number: 11028968
Manufacturer Communication Number: 26-AT-002H
TSB/Document Date: 2026-02-24
Summary
Some Santa Fe (TMA) and Tucson (NX4A) vehicles equipped with a 2.5L GDI engine and 8 speed automatic transmission may have DTC U028700 (Lost Communication With Trans Fluid Pump Module) set by the transmission Electric Oil Pump (EOP). This DTC can cause the Idle Stop & Go (ISG) system to become inoperative. Follow the procedure in this bulletin to replace the Electric Oil Pump on affected vehicles.
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TSB/Document ID: 26-AT-002H
Replacement Service Bulletin Number:
MFR Communication Date: 2026-02-21
MFR Internal Campaign ID/Software Version:
Communication Type: Service Bulletin/Repair Instructions
NHTSA Components: POWER TRAIN
MFR Component System:
MFR Component Subsystem:
Previous TSB | Next TSB |
GROUP
NUMBER
AUTOMATIC
TRANSMISSION
Technical Service Bulletin
SUBJECT:
DATE
26-AT-002H
MODEL(S)
FEBRUARY 2026
SANTA FE (TMA)
TUCSON (NX4A)
ELECTRIC OIL PUMP REPLACEMENT - DTC U028700
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. 10 / 100,000 Powertrain Limited Warranty for
original owners and 5 / 60,000 New Vehicle Limited Warranty (NVLW) for subsequent owners
applies. See Warranty Information section for more details.
Description: Some Santa Fe (TMA) and Tucson (NX4A) vehicles equipped with a 2.5L GDI engine
and 8 speed automatic transmission may have DTC U028700 (Lost Communication With Trans Fluid
Pump Module) set by the transmission Electric Oil Pump (EOP). This DTC can cause the Idle Stop &
Go (ISG) system to become inoperative. Follow the procedure in this bulletin to replace the Electric
Oil Pump on affected vehicles.
Applicable Vehicles:
Model Year
Model
Production Dates
2021 - 2023
Santa Fe (TMA)
11/19/2020 - 12/29/2023
2.5L GDI
2022 - 2024
Tucson (NX4A)
Transmission VIN Starts with
8AT
5NM
02/03/2021 - 09/19/2024
Circulate To: General Manager, Service Manager, Parts Manager, Warranty Manager, Service
Advisors, Technicians, Body Shop Manager, Fleet Repair
ELECTRIC OIL PUMP REPLACEMENT - DTC U028700
SUBJECT:
Parts Information:
Model
Part Name
Part Number
Figure
Remarks
46110-2F600QQH
Applies to 8AT
Transmission
Only
ATF SP4-M1
00232-19107
Qty: 1 Quart
45263-3B000
Qty: 1
45262-3B100
Qty: 1
Eye Bolt Assy
45284-4G800
Qty: 1
Pump Assy Electric Oil
Santa Fe
(TMA)
Tucson
(NX4A)
Warranty Information:
Model
Op. Code
Operation
Tucson (NX4A)
50DA01R0
DTC U028700 and
Electric Oil Pump
(EOP) Replacement
Santa Fe (TMA)
50DA01R1
Op.
Time
Causal Part
0.9 M/H 46110-2F600
Nature
Code
Cause
Code
I11
ZZ3
NOTE 1: Submit claim on Claim Entry Screen as “Campaign” type.
NOTE 2: 10 / 100,000 Powertrain Limited Warranty for original owners and 5 / 60,000 New Vehicle
Limited Warranty (NVLW) for subsequent owners, apply to the part(s) and repair procedure(s)
outlined in this TSB. Prior to beginning any repair work, ensure that the part(s) associated with the
repair procedure are within the applicable warranty, observing mileage and Warranty Start Date or
date of first use. If the subject part(s) are out of warranty coverage, the dealer may 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.
TSB #: 26-AT-002H
Page 2 of 7
SUBJECT:
ELECTRIC OIL PUMP REPLACEMENT - DTC U028700
Service Procedure:
DIGITAL DOCUMENTATION
This TSB includes repair justification in the form of an automatically uploaded DTC via GDS
e-Report at the time of diagnosis. To ensure adherence to the Digital Documentation Policy prior
to claim submission, DTC history can be reviewed via the e-Report function within the GDS.
NOTICE
Applying the recommended torque to all fasteners is essential to reduce potential issues from
occurring after the service procedure.
Service Procedure Flowchart
Vehicle In
Check for DTCs
No
(other DTC)
DTC U028700
set in “Active”
status
TSB does NOT apply.
Follow the normal
diagnostic process.
Yes
Replace the Electric Oil
Pump (EOP) Assembly
Vehicle Out
TSB #: 26-AT-002H
Page 3 of 7
ELECTRIC OIL PUMP REPLACEMENT - DTC U028700
SUBJECT:
DTC Check and EOP Replacement
1.
Using GDS, perform Fault Code Searching in
the AT system for “Active” DTC U028700
(Lost Communication With Trans Fluid Pump
Module).
A
i
Information
DTC U028700 does NOT illuminate a
warning light in the instrument cluster, but
stores the DTC in the transmission
control unit.
•
If DTC U028700 is set in “Active”
status (A), proceed to step 2.
•
If DTC U028700 is NOT in “Active”
status, or another DTC is found, this
TSB does NOT apply. Follow the
normal diagnostic process.
2.
Disconnect the negative (–) battery cable.
3.
Visually check that the lift blocks are properly
seated on the vehicle support points and raise
the vehicle.
U028700
Stored and
No MIL in
Cluster
NOTICE
Raising the vehicle from anywhere other
than the support points may damage
vehicle components.
Refer to the shop manual:
• General Information > Lift and
Support Points > General
Information
TSB #: 26-AT-002H
Page 4 of 7
ELECTRIC OIL PUMP REPLACEMENT - DTC U028700
SUBJECT:
4.
Remove the engine room under cover (B) by
referring to the shop manual:
•
5.
Engine Mechanical System > Engine
and Transmission Assembly >
Engine Room Under Cover >
Removal and Installation
B
Disconnect the electric oil pump (EOP)
connector (C).
C
i
Information
Release the connector hook (D) and then
pull it upward.
D
TSB #: 26-AT-002H
Page 5 of 7
SUBJECT:
6.
ELECTRIC OIL PUMP REPLACEMENT - DTC U028700
Remove the 4 bolts (E) securing the electric
oil pump (EOP) to the transmission and
remove the EOP (F).
Tightening Torque:
7.
lb-ft
18
N.m
23
E
F
E
E
E
Replace the 2 O-rings (G) on the transmission
and install the new EOP in the reverse order
of removal.
Tightening Torque:
8.
lb-ft
18
N.m
23
G
Connect the electric oil pump (EOP)
connector (H).
H
TSB #: 26-AT-002H
Page 6 of 7
ELECTRIC OIL PUMP REPLACEMENT - DTC U028700
SUBJECT:
9.
Add ATF to the specified level according to the
shop manual.
• Automatic Transaxle System >
Automatic Transaxle System >
Automatic Transaxle Fluid (ATF) >
Repair Procedures
i
I
Information
Make sure to add 24 oz. (0.7 liters) of the
proper ATF to the ATF injection hole (I)
before starting the engine.
Check ATF level and check for leaks.
10.
Reinstall all components in the reverse order
of the removal process.
11.
Using GDS, erase DTC history, and perform
Fault Code Searching, confirm DTC
U028700 does NOT set again.
12.
The service procedure is now complete.
TSB #: 26-AT-002H
Page 7 of 7
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