EV Diagnostics
Verified EV diagnostic knowledge page

Genesis P1B77

This service campaign can only be performed at certified EV Genesis Retailers. 2 Recommended Alternative Transportation A Courtesy Vehicle Program (CVP) vehicle or Service Valet sh

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceContact a certified EV Genesis Retailer. The supplied campaign evidence states that this service campaign can only be performed at certified EV Genesis Retailers.
Confidence95%

Quick answer

P1B77 is referenced in Genesis service-campaign materials as a diagnostic trouble code that may occur if an ICCU fuse is installed by itself without replacement of the ICCU assembly. The campaign must be performed by a certified EV Genesis Retailer.

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.

No sufficiently relevant embeddable video has been accepted for this diagnostic yet.

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

1. What does P1B77 mean?

P1B77 is referenced in Genesis service-campaign materials as a diagnostic trouble code that may occur if an ICCU fuse is installed by itself without replacement of the ICCU assembly. The campaign must be performed by a certified EV Genesis Retailer.

2. Technical explanation

Verified Genesis campaign material states that installing an ICCU fuse alone, without replacing the ICCU assembly, can damage the battery PRA and cause DTC P1B77. The supplied evidence does not establish a broader generic definition for P1B77 beyond that documented condition.

3. What system is affected?

The verified material references the ICCU assembly, ICCU fuse, and battery PRA.

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

  • Verified campaign material identifies installation of an ICCU fuse without replacement of the ICCU assembly as a condition that can damage the battery PRA and cause P1B77.

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 assessment through a certified EV Genesis Retailer.
  • Do not rely on an ICCU fuse-only replacement; the verified campaign material states the ICCU assembly must also be replaced when applicable.
  • A Courtesy Vehicle Program vehicle or Service Valet is recommended in the campaign material if ICCU replacement is required.

10. Step-by-step troubleshooting

  1. The verified bulletin includes a DTC check, ICCU software update, and ICCU replacement procedures. These procedures are for certified EV Genesis Retailers.
  2. Do not perform high-voltage or ICCU repair work yourself.

11. When to contact service

Contact a certified EV Genesis Retailer. The supplied campaign evidence states that this service campaign can only be performed at certified EV Genesis Retailers.

12. What the service center may check

  • Check for applicable Genesis service campaign/TSB 23-01-069G or 23-01-069G-1.
  • Perform the bulletin-specified DTC check.
  • Determine whether the applicable bulletin calls for an ICCU software update.
  • If ICCU replacement is required, follow the certified-retailer service procedure.

13. Possible repair or resolution

  • The supplied evidence states not to install an ICCU fuse on its own without also replacing the ICCU assembly.
  • For affected cases described in the campaign, the documented resolution involves ICCU assembly and ICCU fuse replacement.
  • The bulletin also includes an ICCU software update procedure.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Genesis TSB 23-01-069G, published August 15, 2023: https://static.nhtsa.gov/odi/tsbs/2023/MC-10241820-0001.pdf
  • Genesis TSB 23-01-069G, published August 15, 2023: https://static.nhtsa.gov/odi/tsbs/2023/MC-10241817-0001.pdf
  • Genesis TSB 23-01-069G-1, published September 21, 2023, adding GV70 Electrified vehicles: https://static.nhtsa.gov/odi/tsbs/2023/MC-10243370-0001.pdf

16. Recall information

No recall relationship is established by verified evidence.

17. Official manufacturer information

Verified NHTSA-hosted Genesis manufacturer communications identify this as a service campaign handled by certified EV Genesis Retailers. Supplied applicability evidence covers US-market 2023–2024 Genesis GV60 and 2023–2024 Genesis GV70.

19. Frequently asked questions

What does P1B77 mean in the supplied Genesis evidence?

It is a DTC that Genesis campaign material says can result from battery PRA damage if an ICCU fuse is installed without also replacing the ICCU assembly.

Can an ICCU fuse be replaced by itself?

No. The verified Genesis material explicitly states never to install an ICCU fuse on its own without replacing the ICCU assembly, because it can cause battery PRA damage and P1B77.

Which vehicles are covered by the supplied applicability evidence?

US-market 2023–2024 Genesis GV60 and 2023–2024 Genesis GV70. Exact campaign eligibility is not otherwise established by the supplied evidence.

Can any repair shop perform this campaign?

No. The supplied campaign material states it can only be performed at certified EV Genesis Retailers.

20. Sources & verification

Verified
Genesis P1B77: This service campaign can only be performed at… | EV Diagnostics