P1B77 on Hyundai vehicles
P1B77 is named on 8 Hyundai model years (2016–2024): 9 manufacturer filings and 0 owner reports in NHTSA’s files, across Ioniq, Ioniq 5, Ioniq 6, Sonata.
Which Hyundai model years name P1B77
Source: NHTSA manufacturer communications and complaints| Model year | Filed under | Bulletins | Owner reports |
|---|---|---|---|
| 2019 Hyundai Ioniq | Electrical System | 2 | — |
| 2024 Hyundai Ioniq 5 | Electrical System | 1 | — |
| 2024 Hyundai Ioniq 6 | Electrical System | 1 | — |
| 2023 Hyundai Ioniq 5 | Electrical System | 1 | — |
| 2023 Hyundai Ioniq 6 | Electrical System | 1 | — |
| 2022 Hyundai Ioniq 5 | Electrical System | 1 | — |
| 2017 Hyundai Sonata | Electrical System | 1 | — |
| 2016 Hyundai Sonata | Electrical System | 1 | — |
A model year is listed because the code is named in its own record — a bulletin filed against it, or an owner’s complaint about it — not because every one of these vehicles sets it. Counts are documents in NHTSA’s files, not failure rates.
Hyundai filings that name P1B77
Source: NHTSA manufacturer communicationsBulletins and campaigns Hyundai filed with NHTSA whose summary names P1B77. Quote the document number at the service desk — it is a diagnosis the maker has already written down.
- 19-01-023H Service bulletin2019-08-13 · Electrical System — 12V/24V/48V Battery
- This bulletin provides information related to a BMS (Battery Management System) software update to the diagnostic logic for DTC P1B77 ? ?High Voltage Battery Precharging Fault?.
- Campaign T3U Dea Service bulletin2019-08-13 · Electrical System — 12V/24V/48V Battery
- This service campaign provides information related to a BMS software update to the diagnostic logic for DTC P1B77 ? ?High Voltage Battery Pre-charging Fault?.
- 24-EV-004H Service bulletin2024-07-12 · Electrical System
- This bulletin provides important special service instructions to properly repair a vehicle that has been diagnosed to require an Integrated Charge Control Unit (ICCU) replacement, such as required for DTC P1A9096 DC to DC related charging concern or for inoperative AC charging. • The ICCU fuse accessible from a rear side panel of the EV Battery, should NEVER be replaced by itself prior to receivin
- 20-01-003H Service bulletin2020-01-16 · Electrical System
- 2016 - 2017 model year Sonata LF HEV vehicles contain a Power Relay Assembly. The PRA is equipped with a main relay and High Voltage Cable, which in some instances may have a loose connection. If the vehicle continues to operate in this condition, a loose connection could cause a no start condition or a Check Engine and Hybrid Warning Light On with either or both of these DTCs stored: DTC P1B77 H
What P1B77 means
Source: SAE J2012 / OBD-IIP1B77 is a manufacturer-specific code: the second character is a 1, which under the OBD-II standard hands the definition to whoever built the vehicle. The same code can mean one thing on a Ford and something unrelated on a Hyundai. Any site that prints a single definition for it is guessing.
A stored code names the test that failed, never the part that caused it. The record above is what Hyundai and its owners have filed about it; the code’s page across every make has the whole file.
Common questions
Source: NHTSA files and the OBD-II standardIs P1B77 a known problem on Hyundai vehicles?
It is a documented one: NHTSA's files hold 9 manufacturer filings and 0 owner reports naming P1B77 on 8 Hyundai model years (2016–2024). Whether it is a problem on one particular car is a diagnosis, not a count — but a bulletin that names the code on your model year is the place to start.
Which Hyundai models does P1B77 appear on most?
2019 Ioniq (2 documents), 2024 Ioniq 5 (1 document), 2023 Ioniq 5 (1 document).
Does P1B77 on a Hyundai mean it is recalled?
No. Recalls are filed by campaign and matched by VIN; no recall is triggered by a scan tool. Check the VIN at nhtsa.gov/recalls, or open the model year's page here for the campaigns filed against it.