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Hyundai U111788

High Pressure EOP (HP EOP): Refer to the related shop manual to diagnose the DTC. If no wiring harness issues are found, replace the DCT. Model DTC Description 2022~ 2022~ 2022~ 20

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceService need and urgency are not yet established by verified evidence. However, the official communication provides a technician diagnostic path and possible DCT replacement, so qualified Hyundai service is appropriate.
Confidence95%

Quick answer

U111788 is listed by Hyundai as a High Pressure EOP (HP EOP) diagnostic trouble code. The verified Hyundai service communication directs technicians to the related shop manual and states that, if no wiring-harness issue is found, the DCT should be replaced.

This page separates verified manufacturer/regulator evidence from supporting material. Unsupported causes, repairs or safety conclusions are not guessed.

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1. What does U111788 mean?

U111788 is listed by Hyundai as a High Pressure EOP (HP EOP) diagnostic trouble code. The verified Hyundai service communication directs technicians to the related shop manual and states that, if no wiring-harness issue is found, the DCT should be replaced.

2. Technical explanation

The supplied official Hyundai/NHTSA service communication identifies U111788 under High Pressure EOP (HP EOP) information. Its stated diagnostic direction is to use the related shop manual. The communication further states: if no wiring harness issues are found, replace the DCT. The supplied evidence does not establish a more specific failure mechanism for this code.

3. What system is affected?

High Pressure EOP (HP EOP), with the service communication directing diagnosis toward the wiring harness and, if no harness issue is found, DCT replacement.

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

Not yet established by verified evidence.

6. Possible causes

  • A wiring-harness issue is specifically referenced in the verified service communication.
  • If no wiring-harness issue is found, the verified service communication directs replacement of the DCT. No further cause is established by the supplied evidence.

7. Can I still drive the vehicle?

Not yet established by verified evidence.

8. Can I charge the vehicle?

Not yet established by verified evidence.

9. What you can safely do

  • Arrange diagnosis using the related Hyundai shop manual.
  • Have diagnosis and any DCT replacement performed by qualified service personnel.
  • Do not attempt high-voltage or drivetrain repair procedures based on this page.

10. Step-by-step troubleshooting

  1. Use the related shop manual to diagnose U111788, as directed by the verified Hyundai service communication.
  2. Inspect for wiring-harness issues according to the applicable shop-manual procedure.
  3. If no wiring-harness issues are found, the verified communication instructs replacement of the DCT.

11. When to contact service

Service need and urgency are not yet established by verified evidence. However, the official communication provides a technician diagnostic path and possible DCT replacement, so qualified Hyundai service is appropriate.

12. What the service center may check

  • Diagnose U111788 using the related shop manual.
  • Check for wiring-harness issues.
  • If no wiring-harness issue is found, replace the DCT as instructed in the verified communication.

13. Possible repair or resolution

  • If diagnosis finds a wiring-harness issue, the supplied evidence does not specify the repair method.
  • If no wiring-harness issues are found, replace the DCT, per Hyundai communication 22-AT-009H.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Hyundai service communication 22-AT-009H, published through NHTSA as Manufacturer Communication PDF 10217250 on July 14, 2022. It includes U111788 under High Pressure EOP information and directs shop-manual diagnosis; if no wiring-harness issue is found, it directs DCT replacement.

16. Recall information

No recall relationship is established by verified evidence.

17. Official manufacturer information

Verified source: NHTSA Manufacturer Communication PDF 10217250, Hyundai bulletin 22-AT-009H: https://static.nhtsa.gov/odi/tsbs/2022/MC-10217250-0001.pdf

19. Frequently asked questions

What does Hyundai code U111788 mean?

The verified Hyundai communication identifies it as a High Pressure EOP (HP EOP) code.

What does the Hyundai service communication instruct for U111788?

It directs technicians to the related shop manual for diagnosis. If no wiring-harness issue is found, it instructs replacement of the DCT.

Which vehicles are identified in the supplied applicability data?

The supplied data identifies 2022 Hyundai Kona and 2022 Hyundai Santa Fe vehicles in the United States. The supplied evidence does not establish trim, powertrain, or VIN-level applicability.

Is U111788 safe to drive with?

Not yet established by verified evidence.

Is U111788 related to a recall?

No recall information was supplied in the verified evidence.

20. Sources & verification

Verified
Hyundai U111788: High Pressure EOP (HP EOP): Refer to the related shop… | EV Diagnostics