Car Codes diagnostic trouble code
…U replacement part. The ICCU fuse should be replaced at the same time as replacing the ICCU part. o The ICCU fuse function is to protect the EV Battery from a damaged ICCU. o DTC P1B77 Power Relay Assy (PRA) damage in the EV Battery can occur when an ICCU fuse is first replaced without also replacing the ICCU together. o Vehicles with P1B77 require Techline approval for field staff involved EV Battery repair and can result in significant ad…
Code interpretation
What P1B77 means
This code indicates Vehicle fault code with verified manufacturer evidence Its precise meaning depends on the reporting control module, complete failure-type suffix, model year, powertrain and software level.
Driver experience
Symptoms you may notice
A stored diagnostic trouble code or a related system warning.
Test, do not guess
Possible causes
The precise cause depends on the reporting module, vehicle specification, circuit condition and software level.
Evidence-led checks
Recommended diagnostic route
Save the complete scan and confirm the code against model-specific technical information before testing.
- Capture the evidenceSave the complete all-module scan, code suffixes and freeze-frame data.
- Prove the basicsTest battery condition, system voltage, power and grounds.
- Identify the reporterConfirm the module that logged the code and check circuit integrity.
- Compare live dataReview commanded and actual values under the conditions that set the code.
- Test before replacingUse model-specific wiring diagrams, pin tests and technical information.
- Verify the repairClear the code only after recording evidence, then confirm it does not return.
Vehicle fitment
Vehicle applicability
Kia Niro, Hyundai Ioniq 5, Hyundai Ioniq 6, Genesis GV80 Coupe, Genesis GV70, Genesis GV60, Kia Sorento
Before clearing
Can the code be cleared?
Clearing a code without fixing the cause removes useful evidence and may only switch the warning off temporarily. Save the full scan first; a permanent or repeatedly returning code needs testing.
Confirm the suffix, reporting module, model, year, engine and live data before replacing a component.
Verified public evidence
Manufacturer and model coverage
17 public manufacturer records match this search. These records support applicability research but do not replace VIN-specific workshop information.
GV60 EV · 2023 · Powertrain
…U replacement part. The ICCU fuse should be replaced at the same time as replacing the ICCU part. o The ICCU fuse function is to protect the EV Battery from…
SourceGV60 EV · 2024 · Powertrain
…U replacement part. The ICCU fuse should be replaced at the same time as replacing the ICCU part. o The ICCU fuse function is to protect the EV Battery from…
SourceGV70 ELECTRIFIED · 2023 · Powertrain
…U replacement part. The ICCU fuse should be replaced at the same time as replacing the ICCU part. o The ICCU fuse function is to protect the EV Battery from…
SourceGV70 ELECTRIFIED · 2024 · Powertrain
…U replacement part. The ICCU fuse should be replaced at the same time as replacing the ICCU part. o The ICCU fuse function is to protect the EV Battery from…
SourceGV80 EV · 2023 · Powertrain
…U replacement part. The ICCU fuse should be replaced at the same time as replacing the ICCU part. o The ICCU fuse function is to protect the EV Battery from…
SourceGV80 EV · 2024 · Powertrain
…U replacement part. The ICCU fuse should be replaced at the same time as replacing the ICCU part. o The ICCU fuse function is to protect the EV Battery from…
SourceIONIQ 5 · 2022 · Powertrain
…U replacement part. The ICCU fuse should be replaced at the same time as replacing the ICCU part. o The ICCU fuse function is to protect the EV Battery from…
SourceIONIQ 5 · 2023 · Powertrain
…U replacement part. The ICCU fuse should be replaced at the same time as replacing the ICCU part. o The ICCU fuse function is to protect the EV Battery from…
SourceIONIQ 5 · 2024 · Powertrain
…U replacement part. The ICCU fuse should be replaced at the same time as replacing the ICCU part. o The ICCU fuse function is to protect the EV Battery from…
SourceIONIQ 6 · 2023 · Powertrain
…U replacement part. The ICCU fuse should be replaced at the same time as replacing the ICCU part. o The ICCU fuse function is to protect the EV Battery from…
SourceIONIQ 6 · 2024 · Powertrain
…U replacement part. The ICCU fuse should be replaced at the same time as replacing the ICCU part. o The ICCU fuse function is to protect the EV Battery from…
SourceNIRO · 2018 · Powertrain
TSBELE185: SERVICE ACTION: DE HEV BMS DTC (P1B77) JUDGEMENT LOGIC IMPROVEMENT (SA393) - This bulletin provides the procedure to improve the logic of the Body Control Module (BCM) on some…
SourceNIRO · 2019 · Powertrain
TSBELE185: SERVICE ACTION: DE HEV BMS DTC (P1B77) JUDGEMENT LOGIC IMPROVEMENT (SA393) - This bulletin provides the procedure to improve the logic of the Body Control Module (BCM) on some…
SourceNIRO HYBRID · 2017 · Powertrain
PITSTOP: Voltage Protection Device (VPD) DTCs P1BA7 and P1B77 - The Voltage Protection Device (VPD) (1) is mounted on top of the HV battery pack. If the HV battery overcharges,…
SourceNIRO · 2017 · Powertrain
PITSTOP - HEV WARNING LIGHT AND DTC P1B25/P1B77 - This bulletin has been revised to include additional information. When addressing a concern related to the Niro HV warning light ON,…
SourceNIRO · 2017 · Powertrain
PITSTOP - HEV WARNING LIGHT AND DTC P1B25/P1B77 - When addressing a concern related to the Niro HV warning light ON, and KDS detects a primary DTC P1B25 (HV Path…
SourceSORENTO HYBRID · 2025 · Powertrain
…uced from March 4, 2024 through November 9, 2024. The affected vehicles may exhibit traction motor noise, an inoperable A/C, and illuminated warning lights with DTCs P0A3C, P0AF0, P1B77 stored…
Source