SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/cdl-low-air-warning-stop

The low air pressure warning comes on while you are driving. What should you do?

Stop and safely park as soon as possible.

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  1. Keep driving until the spring brakes come on
  2. Pump the brake pedal to build pressure
  3. Stop and safely park as soon as possible ✔

Why: There may be an air leak. You can only brake under control while there is enough air in the tanks, so stop while the foot brake still works.

Huh, didn't know that: Lightly loaded trucks or trucks on slippery roads may skid when the spring brakes come on.

The dad joke
Why did the trucker stop at the rest area? The sign said rest, and he never argues with a sign.
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References

Answer: Stop and safely park as soon as possible. There may be an air leak. You can only brake under control while there is enough air in the tanks, so stop while the foot brake still works.

  1. California Commercial Driver Handbook (DMV) www.dmv.ca.gov/portal/file/california-commercial-driver-handbook-pdf
    If the low air pressure warning comes on, stop and safely park your vehicle as soon as possible.
    Checked 2026-10-10.

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Test yourself in the game

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