Free CDL cheat sheet
Air Brakes on One Page
Every air brake number and check you need for the permit test, on one printable page.
Air Brakes on One Page
Key numbers
| What | Number |
|---|---|
| Governor cut-out (compressor stops) | about 125 psi |
| Governor cut-in (compressor starts) | about 100 psi |
| Low air warning comes on | before pressure falls below 55 psi |
6 more numbers, the 7 step air brake check and 6 test traps are on the full page.
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