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Hyundai U004688

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 diagnosis is appropriate because the verified procedure requires shop-manual diagnosis and may lead to DCT replacement.
Confidence95%

Quick answer

U004688 is listed by Hyundai as an HP EOP-related diagnostic code. The verified instruction is to use the related shop manual for diagnosis; if no wiring-harness issue is found, replace the DCT.

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 U004688 mean?

U004688 is listed by Hyundai as an HP EOP-related diagnostic code. The verified instruction is to use the related shop manual for diagnosis; if no wiring-harness issue is found, replace the DCT.

2. Technical explanation

The supplied Hyundai/NHTSA service communication identifies U004688 in the High Pressure EOP (HP EOP) diagnostic information. The communication states: “Refer to the related shop manual to diagnose the DTC. If no wiring harness issues are found, replace the DCT.” The supplied evidence also lists U004688 alongside “CAN2 BUS OFF + CAN3 BUS OFF together.”

3. What system is affected?

High Pressure EOP (HP EOP) and associated CAN communication/DCT diagnostic context.

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 diagnostic instruction.
  • If no wiring-harness issue is found, the verified instruction directs replacement of the DCT.

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.
  • Do not attempt high-voltage or DCT repair based on this page.

10. Step-by-step troubleshooting

  1. Have a qualified service facility diagnose U004688 using the related shop manual.
  2. Inspect for wiring-harness issues as directed by the verified service communication.
  3. If no wiring-harness issue is found, the communication directs replacement of the DCT.

11. When to contact service

Service diagnosis is appropriate because the verified procedure requires shop-manual diagnosis and may lead to DCT replacement.

12. What the service center may check

  • Diagnose U004688 according to the related shop manual.
  • Check for wiring-harness issues.
  • If no wiring-harness issue is found, replace the DCT.

13. Possible repair or resolution

  • The verified service communication directs DCT replacement when no wiring-harness issue is found.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Hyundai service communication 22-AT-009H, published through NHTSA as Manufacturer Communication PDF 10217250 on 2022-07-14. It includes U004688 within HP EOP diagnostic information and provides the diagnostic instruction cited above.

16. Recall information

No recall relationship is established by verified evidence.

17. Official manufacturer information

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

19. Frequently asked questions

What does U004688 mean?

The verified Hyundai communication lists U004688 in HP EOP diagnostic information and alongside “CAN2 BUS OFF + CAN3 BUS OFF together.”

What is the verified repair direction for U004688?

Use the related shop manual to diagnose the DTC. If no wiring-harness issue is found, replace the DCT.

Which vehicles are established by the supplied applicability data?

2022 Hyundai Kona and 2022 Hyundai Santa Fe vehicles in the US. The supplied communication excerpt also references other models, but their applicability to this specific record is not established by the supplied applicability data.

20. Sources & verification

Verified
Hyundai U004688: High Pressure EOP (HP EOP): Refer to the related shop… | EV Diagnostics