A car pedal looks simple: a metal arm, a pad and a hinge. But it is the part your foot trusts in an emergency. If it bends, cracks or sticks, nothing else in the brake system can help.
In China, the bench tests for brake and clutch pedals come from one document: QC/T 788-2018. If you make pedal assemblies for Chinese carmakers, or you buy them from Chinese suppliers, this is the standard behind the test report on your desk. Here is what it checks, with the real numbers.
In short
- What it is
- China's automotive industry standard for pedal assemblies: performance requirements and bench test methods
- Chinese title
- 汽车踏板装置性能要求及台架试验方法
- Covers
- Mechanical, hinged, metal brake pedals and clutch pedals
- Does not cover
- Accelerator pedals (removed from the scope in 2018)
- Issued by
- Ministry of Industry and Information Technology (MIIT)
- Dates
- Issued July 4, 2018 · in force since January 1, 2019
- Replaces
- QC/T 788-2007
What is QC/T 788-2018?
The code tells you a lot. QC stands for qiche, the Chinese word for car: it is an automotive industry standard. The /T means "recommended", not mandatory by law.
"Recommended" can sound optional. In practice, carmakers often write QC/T 788 into their technical agreements with pedal suppliers. From that moment, passing the tests is a delivery condition, and the test report is part of the deal.
The standard applies to mechanical, hinged, metal brake and clutch pedals. Other kinds of pedal device can use it as a reference.
What changed from the 2007 edition?
| Topic | QC/T 788-2007 | QC/T 788-2018 |
|---|---|---|
| Accelerator pedal | Covered | Removed from the scope |
| Vibration durability | No test | New test; the brake or clutch light switch must not switch on |
| Before testing | Not specified | Operate each sample 5 times first |
| Room temperature for tests | Not specified | 8 °C to 38 °C, unless a test says otherwise |
| Heat and cold tests | "Workability" | "Adaptability", with a new measurement after the test |
| Strength and corrosion | Older test conditions | New strength conditions and a new corrosion test time |
The tests, one by one
QC/T 788 puts a pedal through eight checks. Here is what each one looks for, and the headline limits:
| Test | What it checks | Headline limit |
|---|---|---|
| Play (front-to-back and side-to-side) | How much the pedal moves when it should not | Set in clause 4.1 |
| Torsion | The pad is twisted around its main weld | No cracks or damage |
| Strength | A heavy load on the pedal | Permanent bending 5.0 mm or less, no cracks |
| Working durability | Years of pushing, compressed into a bench test | Play afterwards 4.0 mm front-to-back, 6.0 mm side-to-side, at most |
| Vibration durability (new) | The pedal is shaken like on a rough road | The brake or clutch light switch must never switch on |
| Heat | The pedal must work after a long time at 80 °C | No sticking, rubbing or noise |
| Cold | The same at −40 °C | No sticking, rubbing or noise |
| Corrosion | Salt spray test | Only a few small rust spots allowed |
The forces, torques, times, cycle numbers and exact pass criteria for each test are in clauses 4 and 6 of the standard, with the drawings of each test set-up.
An example
Imagine your brake pedal goes through the tests. In the strength test it bends permanently by 3.2 mm: that is fine, the limit is 5.0 mm. After the durability test it has no cracks, but the side-to-side play is now 6.4 mm. That is a fail, even though nothing is broken. The limit is 6.0 mm.
This is the most common surprise. A pedal can look perfect and still fail on play. Worn bushings and a loose pivot are usually the cause.
Test rules that labs sometimes get wrong
Clause 5 sets the ground rules for every test: how many samples, when the return spring comes off, how to prepare the samples, the room temperature and how accurate the instruments must be. A report that ignores them can be rejected, even if the pedal is good.
If a test report doesn't say how many samples were used, or how they were prepared, ask. A customer's quality team will.
Why does the brake light switch matter in a vibration test?
Many pedals carry a small switch that turns on the brake lights. If road vibration makes it switch on by itself, the brake lights flash with nobody braking. Drivers behind you get the wrong message, and the car's computers can think you are braking too. Since 2018, the switch must stay quiet during the whole vibration test.
What about accelerator pedals?
They are no longer in QC/T 788. The 2018 edition removed them, so a test report to QC/T 788-2018 says nothing about your accelerator pedal.
The brake pedal, meanwhile, stays at the centre of everyday driving in China. The new braking standard GB 21670-2025 limits one-pedal driving in the default mode of electric cars, so drivers keep using the brake pedal. Read our explainer on GB 21670-2025.
Who needs QC/T 788-2018?
- Pedal and pedal-box makers supplying Chinese carmakers
- Carmakers' purchasing and quality teams writing pedal specifications
- Test laboratories running pedal bench tests
- Buyers of pedals made in China who need to read and check the supplier's test report
What should you do now?
- Check the scope. Brake or clutch pedal, mechanical and hinged? Then QC/T 788-2018 is your reference.
- Plan all eight tests, including the vibration test added in 2018.
- Watch the play limits after durability: 4.0 mm front-to-back, 6.0 mm side-to-side.
- Check the switch during the vibration test, not only after it.
- Read the report closely against the test rules in clause 5.
The figures above are the headline limits. To plan or check the tests, your engineers and your lab need the full text: the loads in Table 1, the play limits for new pedals, the test methods and the drawings.
Get the full English version of QC/T 788-2018 — invoice included. Need it for a supplier audit or a test plan? Tell us and we'll help.