EV Diagnostics
Verified EV diagnostic knowledge page

Hyundai P0734

This TSB provides a procedure to diagnose and repair a transaxle for the following Incorrect Ratio DTC (transaxle clutch slipping more than 200 rpm in gear). DTC Description P0731

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceHyundai service is appropriate because the official bulletin provides a transaxle diagnostic and repair procedure for P0734.
Confidence95%

Quick answer

P0734 is identified in Hyundai’s official transaxle bulletin as “Gear 4 incorrect ratio” (P073400). The bulletin describes these incorrect-ratio DTCs as transaxle clutch slipping more than 200 rpm while in gear.

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

Video guides

Watch Videos

Relevant videos play here without leaving this diagnostic page.

DTC Code P0734 Hyundai/Slipping Transmission Fix WITTJamie Jones TheCarMan

Videos are supporting material and never override OEM or regulator evidence.

1. What does P0734 mean?

P0734 is identified in Hyundai’s official transaxle bulletin as “Gear 4 incorrect ratio” (P073400). The bulletin describes these incorrect-ratio DTCs as transaxle clutch slipping more than 200 rpm while in gear.

2. Technical explanation

Hyundai TSB 19-AT-012H / 20-AT-001H provides a diagnostic and repair procedure for transaxle incorrect-ratio DTCs. For P0734, the listed description is “Gear 4 incorrect ratio” / “P073400.” The bulletin’s description states that the relevant condition is transaxle clutch slipping more than 200 rpm in gear.

3. What system is affected?

Transaxle.

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

  • The verified bulletin identifies the monitored condition as transaxle clutch slipping more than 200 rpm in gear. Specific underlying causes are not yet established by the supplied verified 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 Hyundai’s applicable official transaxle procedure.
  • Do not attempt high-voltage or transaxle repair procedures without qualified service support.

10. Step-by-step troubleshooting

  1. Use Hyundai TSB 19-AT-012H / 20-AT-001H as the applicable diagnostic and repair reference where vehicle applicability is confirmed.
  2. The supplied evidence does not establish user-performed diagnostic steps.

11. When to contact service

Hyundai service is appropriate because the official bulletin provides a transaxle diagnostic and repair procedure for P0734.

12. What the service center may check

  • Confirm the stored DTC is P0734/P073400.
  • Follow the diagnostic and repair procedure in Hyundai TSB 19-AT-012H / 20-AT-001H when applicable.

13. Possible repair or resolution

  • The official bulletin states that it provides a procedure to diagnose and repair the transaxle for P0734 and the listed incorrect-ratio DTCs. Specific repair outcomes are not established by the supplied evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Hyundai TSB 20-AT-001H, published January 2, 2020. NHTSA manufacturer communication 10170899: https://static.nhtsa.gov/odi/tsbs/2020/MC-10170899-0001.pdf
  • Hyundai TSB 19-AT-012H, published June 4, 2019. NHTSA manufacturer communication 10163279: https://static.nhtsa.gov/odi/tsbs/2019/MC-10163279-9999.pdf

16. Recall information

No recall relationship is established by verified evidence.

17. Official manufacturer information

Verified official evidence consists of Hyundai manufacturer communications published by NHTSA. Supplied applicability records list US Hyundai Kona model years 2016–2019 and 2016–2020, and US Hyundai Sonata model years 2016–2019 and 2016–2020. Because these ranges overlap and no VIN-level applicability is supplied, confirm applicability with Hyundai before relying on the bulletin for a specific vehicle.

19. Frequently asked questions

What does Hyundai P0734 mean?

In the verified Hyundai bulletin, P0734/P073400 means “Gear 4 incorrect ratio.”

What condition does the Hyundai bulletin associate with P0734?

The bulletin describes the incorrect-ratio DTC condition as transaxle clutch slipping more than 200 rpm in gear.

Is P0734 covered by a recall?

Not yet established by verified evidence.

Is it safe to drive or charge with P0734?

Not yet established by verified evidence.

20. Sources & verification

ReferenceVerified
Hyundai P0734: This TSB provides a procedure to diagnose and repair a… | EV Diagnostics