Problems · NHTSA complaints
2020 Hyundai Ioniq Plug-in Hybrid problems
Owners filed 6 complaints about the 2020 Hyundai Ioniq Plug-in Hybrid with NHTSA between Aug 2020 and Oct 2026. The most-cited component is service brakes (2).
Complaints
6
Filed with NHTSA
Crashes
2
Reported by owners
Fires
1
Reported by owners
Injuries
1
People reported injured
Deaths
0
Reported to NHTSA
Complaints by component
One complaint can cite several components
- Service brakes2
- Engine1
- Power train1
- Forward collision avoidance1
- Visibility/wiper1
- Other / unknown1
Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.
Data from NHTSA Complaints API · synced Nov 13, 2026NHTSA vehicle page
When complaints were filed
Does it get worse with age? Complaints per calendar year filed
1
0
0
0
1
1
3
View as table
| Model year | Complaints filed per calendar year |
|---|---|
| 2020 | 1 |
| 2021 | 0 |
| 2022 | 0 |
| 2023 | 0 |
| 2024 | 1 |
| 2025 | 1 |
| 2026 | 3 |
Mileage at failure isn’t a structured field in NHTSA complaint data, so we don’t chart it. Some owners mention it in their reports below.
Top problems in owners’ words
Verbatim from NHTSA complaints, newest first
Service brakes
2 reports1 crash1 fire
“I leased the vehicle in 03-2021 and within the first year took the car back to the dealer 3 times for complaint on braking system. The brake pedal would loose pressure and stopping distance would extend further than anticipated. the dealer consistently told me that they could not duplicate the problem. now has gotten to the point that EBP light and HOLD light stay on steady and red Brake light flashes, due to this the smart cruise control and crash avoidance system become inoperable. Recently became aware that this issue is known to Hyundai and they have TSB for this issue, TSB # 23-BR-001H which describes the problem with rear caliper harness contamination with moisture. now that my vehicle has passed the 36K miles warranty, dealer wants to charge about $2000 for repairs. Currently have 39685 miles on the vehicle.”
Engine
1 report
“The engine coolant can leak into the exhaust because air a known design flaw. When the the engine turns on after being in electric mode the coolant pump starts and pushes it out the exhaust causing a sudden over heating of the engine. This causes the car to stall and can be very dangerous at freeway speeds.”
Power train
1 report1 crash
“When the engine is turned off, and the car is not in park, it rolls. When the engine is turned off the car should automatically switch to P to prevent it from rolling. Our car was left in R with the engine off. And instead of switching to P automatically, it just rolled away and hit the neighbors garage.”
Forward collision avoidance
1 report
Visibility/wiper
1 report
“The display does not always show reverse camera when backing up. Not often, but does occur. I can use mirrors, etc. Annoying as it is a learned experience with this car, and when reverse camera is not operational it does limit view behind car due to design. I did capture video this time as it isn't first occurrence. I was in parking lot where I could do this without endangering anyone.”
Data from NHTSA Complaints API (owner reports, unverified) · synced Nov 13, 2026
Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.