If you build cars, brake systems or car software for China, pay attention: the braking rulebook has changed. And one of the changes touches a feature many electric car drivers love — one-pedal driving.
The new rulebook is GB 21670-2025. It replaces GB 21670-2008, which was in place for 17 years. It is mandatory, it has applied since January 1, 2026, and the last parts arrive in early 2027. Here is what it says, in plain words.
In short
- What it is
- China's mandatory national standard for passenger car braking systems
- Chinese title
- 乘用车制动系统技术要求及试验方法
- Applies to
- Category M1 vehicles (passenger cars)
- Replaces
- GB 21670-2008
- Published
- May 30, 2025, by SAMR and the Standardization Administration of China
- In force
- January 1, 2026 for new type approvals; early 2027 for models already approved
- Biggest changes
- One-pedal driving can't be the default · ABS on every car · brake lights must turn on with regenerative braking above 1.3 m/s² · new rules for fully electric brakes
What is GB 21670-2025?
It is the Chinese standard that says how the brakes of a passenger car must work, and how they are tested. It covers the service brake (the normal brake pedal), the emergency brake, the parking brake, ABS, warning lights and brake lights.
Every passenger car needs to pass it to get type approval in China. The code starts with GB, not GB/T — that means it is compulsory, not a recommendation.
Why a new version? The 2008 text was written before most cars had electric motors, regenerative braking and electronic parking brakes. The 2025 text catches up. Its foreword lists more than 70 technical changes compared to 2008.
What changed from GB 21670-2008?
These are the changes that matter most in practice:
| Topic | GB 21670-2008 | GB 21670-2025 |
|---|---|---|
| One-pedal driving | Not regulated | Can't stop the car in the default mode; max 3 m/s²; resets at every start |
| ABS | Not required on every car | Required on all passenger cars |
| Brake lights with regen or automatic braking | General rules | Must turn on above 1.3 m/s², must not flicker |
| Emergency braking signal (flashing lights) | Not covered | If fitted: never below 6 m/s², off below 2.5 m/s² |
| Fully electric brakes (ETBS) | Not covered | New special rules on battery state, warnings and braking after switch-off |
| Electronic parking brake fault | Older version of the rule | Must still hold a fully loaded car on an 8% slope |
| Temporary spare wheel | Not covered | New braking test with the spare wheel fitted |
| Functional safety of brake electronics | Older appendix | New documentation and test report rules, based on GB/T 34590 (China's version of ISO 26262) |
Some old parts were removed: the rules on braking force distribution between axles, the tests for class 2 and class 3 ABS, and the inertia dynamometer test for brake linings.
What does the one-pedal driving rule actually say?
Many electric cars let you slow down and even stop just by lifting your foot off the accelerator. In city traffic it feels great. China is not banning it. It is changing what the car does by default. Clause 5.2.18 f) says:
- In the default mode, lifting the accelerator alone must not bring the car to a full stop.
- In the default mode, the slowdown from regenerative braking can be at most 3 m/s².
- Every time the car is switched on, it must go back to the default mode (or to a mode the driver has set up).
- If a stronger mode is active, a light must stay on to show it.
- The owner's manual must explain how to change the modes.
So the driver can still choose one-pedal driving. The car just can't start that way.
Why? The people who wrote the standard are worried about pedal confusion. If your right foot does everything on one pedal, in a panic you may press the accelerator when you mean to brake. Keeping the brake pedal in the loop keeps the reflex alive.
When do the new rules apply?
| Date | What happens |
|---|---|
| May 30, 2025 | Standard published |
| January 1, 2026 | In force for new type approvals — all rules except two |
| 13 months later (early 2027) | New type approvals must also meet the one-pedal rule and the parking brake fault rule |
| From the 13th month (early 2027) | Models that already have type approval must meet the whole standard |
In short: by early 2027, every new passenger car sold in China must meet the full standard — including models that are already on sale today.
Who needs to pay attention?
- Electric and hybrid car makers — regenerative braking, one-pedal modes, brake light logic
- Brake system suppliers — ABS, electronic parking brakes, brake-by-wire
- Software teams — many of these changes are a software update: default modes, reset at start, brake light thresholds
- Importers of foreign-built cars sold in China
- Test labs and homologation teams preparing type approval files
Is a European (UN R13-H) approval enough for China?
No. GB 21670 covers similar ground to the UN rules for passenger car brakes, but it is a separate Chinese standard with its own tests and its own extra rules — like the one-pedal default limit. To sell in China, the car has to be tested against GB 21670-2025 itself.
What should you do now?
- Check your one-pedal modes. Default mode: no full stop, max 3 m/s², reset at every start, a light for other modes, and an updated manual.
- Check your brake light logic. On above 1.3 m/s² from regen or automatic braking, and no flickering.
- Confirm ABS on every version of every M1 model, base versions included.
- Test the electronic parking brake fault case: a fully loaded car must stay still on an 8% slope.
- Working on brake-by-wire (ETBS)? Read clause 5.2.24 and the new battery and warning tests.
- Update your functional safety documents to the new format in Appendices A, B and C.
- Plan re-testing for models already on sale before the early 2027 deadline.
One last thing: the official text is published in Chinese only. Your engineers need the exact clauses and numbers, not a news summary — and our English translation runs to 124 pages.
Get the full English PDF of GB 21670-2025 now — instant download, invoice included.
Need to know exactly what changed for your car? We can compare the 2008 and 2025 editions clause by clause against your design. See our gap analysis service.