GROUP
Fuel System

Technical Service Bulletin
SUBJECT:

DATE
JUNE 2023

NUMBER
23-FL-004H

MODEL
SONATA (LFA)

FUEL PUMP FILTER WARRANTY EXTENSION (TXXS),
INSPECTION AND REPLACEMENT

Description: Certain 2015-2019MY Sonata (LFA) vehicles may intermittently exhibit reduced engine
power, a “Crank/No Start” condition, and/or have DTC P1233 stored in the ECM due to an internally
leaking fuel pump filter housing.
Hyundai is extending warranty coverage for fuel pump filter assembly repair or replacement to 15
years / 150,000 miles from the date of original retail delivery or date of first use (whichever occurs
first) and is valid for original and subsequent owners.
Follow the service procedure to inspect the low-pressure fuel pump operation and replace the fuel
filter if necessary.
DTC Description:
P1233: Low Pressure Fuel System – High Deviation between target and current pressure.

Applicable Vehicles (Certain):
2015-2019 Sonata (LFA) vehicles produced 05/01/2014 - 09/30/2019 with VINs starting with "5NP"
Parts Information:
PART NAME
PART NUMBER


FUEL FILTER
ASSEMBLY

31112-C2500

O-RING

31123-B9000

(Fuel Pump Top Plate)

NOTES
Replace fuel filter only under these criterias:
If vehicle has DTC P1233 stored in ECU.

OR



If vehicle experiences related symptoms (reduced engine
power or crank/no start) and fuel pump actuation test
inspection is NO PASS.

Replace if damaged during new fuel filter assembly installation.

Circulate To: Service Manager, Warranty Manager, Service Advisors, Technicians, Fleet Repair

SUBJECT: FUEL PUMP FILTER WARRANTY EXTENSION (TXXS), INSPECTION AND REPLACEMENT

SST Information:
DESCRIPTION

PART NUMBER

Fuel Pressure Gauge

09353-24100
(or equivalent)

Fuel Pressure Gauge Adapter

09353-02100
(or equivalent)

FIGURE

Warranty Information:
MODEL

OP CODE

OPERATION

OP
TIME

20DA27R0

Fuel Filter Diagnosis Inspection Only
(Procedure A)

0.3 M/H

Sonata (LFA)
 15MY-19MY
2.0T & 2.4L
 15-17MY 1.6T

Sonata (LFA)
 18-19MY 1.6T

Sonata (LFA)

 All Engines

Sonata (LFA)

 All Engines

20DA27R1
20DA27R2

Fuel Filter Diagnosis Inspection Only
(Procedure B)
Fuel Filter Diagnosis
and Replacement

0.3 M/H

CAUSAL P/N

NATURE
CODE

CAUSE
CODE

31112-C2500

B25

ZZ4

0.8 M/H

(Existing O-Ring reused)

20DA27R3

Fuel Filter Diagnosis
and Replacement

0.8 M/H

(New O-Ring installed)

NOTE 1: If the affected parts are still under factory warranty, submit as normal warranty. If the affected
parts are out of factory warranty and within the extended warranty period, submit as a campaign claim
type using the op codes listed above.
NOTE 2: If a part that is not covered by this TSB is found in need of replacement while performing
TXXS and the affected part is still under warranty, submit a separate claim using the same repair
order. If the affected part is out of warranty, submit a Prior Approval request for goodwill consideration
prior to performing the work.
NOTE 3: Labor OP code 20DA27R3 will reimburse for new O-ring if existing O-ring is damaged during
new fuel filter assembly installation.
NOTE 4: Op times include VIN, Mileage, and Part (if applicable) validation. All claims submitted that
have incomplete, illegible, or missing documentation are subject to debit.
NOTE 5: The incident parts are subject to callback through normal Warranty Technical Center (WTC)
parts return process. Claim is subject to debit if the part is not returned.

TSB #: 23-FL-004H

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SUBJECT: FUEL PUMP FILTER WARRANTY EXTENSION (TXXS), INSPECTION AND REPLACEMENT

STUI
As outlined in the Digital Documentation Policy, all claims require VIN and Mileage validation
through VCI connection or photo capture, AND photo capture of the repair Part according to the
steps in the TSB. All claims submitted that have incomplete, illegible, or missing
documentation are subject to debit.

Service Process Overview:

Service Procedure:
1. Using GDS, check vehicle if DTC P1233 is present.
 If DTC P1233 is detected, then skip directly to Fuel Filter Replacement.
 If there are other related symptoms with no DTC P1233, then follow the appropriate
Inspection Test Procedure below:



15MY-19MY Sonata (LFA) w/ 2.0T & 2.4L engine
15-17MY Sonata (LFA) w/ 1.6T engine

Inspection Test Procedure A



18-19MY Sonata (LFA) w/ 1.6T engine

Inspection Test Procedure B

TSB #: 23-FL-004H

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SUBJECT: FUEL PUMP FILTER WARRANTY EXTENSION (TXXS), INSPECTION AND REPLACEMENT

*** Inspection Test Procedure A ***
2. Shut engine “OFF” for at least 3 minutes.
3. Afterwards, turn ignition switch to “ON” position.
NOTE: DO NOT start the engine.

 Absolute Electrical Fuel Pump Low
Pressure Active Value.

4. Using the GDS, select “Data Analysis” and
highlight the two items listed on right.

 Absolute Electrical Fuel Pump Low
Pressure Set Point.

5. Select “Text” and change to “Graph”.
6. Select “Actuation Test” tab and “Fuel Pump
Relay” item.
7. Start the actuation of the Fuel Pump Relay and
observe the “Absolute Electrical Fuel Pump Low
Pressure Active Value” on the graph.
 PASS: Graph displays five (5) or more even
and continuous bars of pressure [OK], then
no further action is required. Inspection is
complete. (Continue normal diagnosis of
abnormal condition if it still exists.)

STUI


Take a screenshot of the 'PASS' result
using your particular tablet's
screenshot save method and upload to
STUI.

NO PASS: Graph displays uneven bars
[NG], then follow the Fuel Filter
Replacement procedure at step 10.

*** Inspection Test Procedure B ***
8. Release the residual pressure in fuel line by
referring to the Shop Manual: Engine Control /
Fuel System > Fuel Delivery System > Repair
Procedure > Release Residual Pressure in
Fuel Line.
NOTE: Follow all cautions according to the
Shop Manual.
9. Check fuel pressure at idle by referring to the
Shop Manual: Engine Control / Fuel System >
Fuel Delivery System > Repair Procedure >
Fuel Pressure Test (Low Pressure System),
then shut engine off while monitoring the gauge.

TSB #: 23-FL-004H

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SUBJECT: FUEL PUMP FILTER WARRANTY EXTENSION (TXXS), INSPECTION AND REPLACEMENT

 PASS: If fuel pressure gauge reading
remains above 14.5 PSI for at least 1 minute,
then inspection is complete. (Continue
normal diagnosis of abnormal condition if it
still exists.)

 NO PASS: If fuel pressure gauge
reading drops below 14.5 PSI within 1
minute, then follow the Fuel Filter
Replacement procedure at step 10.

STUI
Using STUI, take a photo of the fuel
gauge reading with last 6-digits of VIN
and date of repair on a piece of paper.
Ensure the picture is in focus and VIN
with date of repair are legible. Upload
the photo in STUI.
*** Fuel Filter Replacement ***
10. Release the residual pressure in fuel line by
referring to the Shop Manual: Engine Control /
Fuel System > Fuel Delivery System > Repair
Procedure > Release Residual Pressure in
Fuel Line.
11. Remove the fuel pump assembly by referring to
the Shop Manual: Engine Control / Fuel
System > Fuel Delivery System > Fuel Pump.

D

C

12. Remove the fixing clip (C) and then disconnect
the fuel tube (D).
NOTE: Do not discard this O-ring (E).
The O-ring shown here must be reused.

E

TSB #: 23-FL-004H

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SUBJECT: FUEL PUMP FILTER WARRANTY EXTENSION (TXXS), INSPECTION AND REPLACEMENT

13. Remove the fuel pressure regulator-fixing clip
(F).
14. Remove the fuel pressure regulator (G) from the
fuel filter.
15. Release the fixing hook (H), and then remove
the fuel filter (I).

G
F

I
H

J
16. Remove the O-Ring (J) off the existing fuel filter
assembly and install on the new fuel filter
assembly.

STUI
Using STUI in the GDS, take a picture of
the NEW fuel filter with last 6-digits of VIN
and date of repair on a piece of paper.
Ensure the picture is in focus and VIN with
date of repair are legible.
Upload the photo in STUI.

VIN: 123456
Date: 7/7/2023

TSB #: 23-FL-004H

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SUBJECT: FUEL PUMP FILTER WARRANTY EXTENSION (TXXS), INSPECTION AND REPLACEMENT

17. Install in the reverse order of removal.
NOTES:
 When installing the new fuel filter assembly,
make sure the orientation of the fixing hook
(H) shown in step 15 is correct.
 When reinstalling the fuel pump assembly
into the fuel tank, inspect the O-ring (K) for
the top plate and reuse. If O-ring appears
damaged, then replace with a new part.
 (O-Ring Part Number: 31123-B9000)

K

18. Repair Procedure is now complete.

TSB #: 23-FL-004H

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