*Some states have different testing requirements, make sure to consult your state's CDL manual to confirm this material is accurate for your state.

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Step 1: Turn the Key to the "On" Position

Say out loud: “I will turn the key to the on-position.”

• Turn the key to the ON position without starting the engine.
  
  

Step 2: Fan the Service Brake Below 90 PSI

Say out loud: “I will now fan the service brakes below 90 PSI so my air governor kicks on when I start the truck.”

• Press and release the service brake (foot brake) repeatedly until air pressure drops below 90 PSI.
• This ensures the air governor will kick on when the truck starts.
• (If air pressure is already below 90 PSI, continue to the next step.)
  
  

Step 3: Identify Air Pressure Levels

Say out loud: “The PRIMARY air gauge is at ______, and the SECONDARY air gauge is at ______.”

• Record the current air pressure readings.
  
  

Step 4: Perform a Safety Start

Say out loud: “I will perform a safety start.”
A. Say each step while performing it:

• “I will press in the clutch.”
• “I will verify the gear shifter is in neutral.”
• “I will turn the key to the on position.”
• “The ABS light came on and turned off; I will start the truck.”
• “I will listen for my air governor to cut out between 120-140 PSI.”
  B. Wait for air pressure to build.
  C. Once cut-out occurs, say out loud:
• “The PRIMARY air gauge cut out at _____, and the SECONDARY air gauge cut out at _____.”
  D. Secure the truck and verify ABS light again:
• “I will place the truck in gear so it does not roll away.”
• “I will turn the truck off and then turn the key to the on position.”
• “I will check that the ABS light comes on and turns off.”
  
  

Step 5: Fill the Air Chambers

Say out loud: “I will PRESS in the truck and trailer air valves and WAIT for the air chambers to fill.”

• Press in both the truck and trailer air valves.
• Wait for the air chambers to fill.
• The air pressure needles will stop moving once the chambers are full.
  
  

Step 6: Apply and Hold the Service Brake

Say out loud: “I will now PRESS and HOLD the service brake.”

• Press and hold the service brake (foot brake).
  
  

Step 7: Check and Record Air Pressure

Say out loud: “The PRIMARY gauge is at _____ and the SECONDARY gauge is at _____.”

• Record the air pressure levels after pressing the service brake.
  
  

Step 8: Monitor Air Pressure Loss Over 60 Seconds

Say out loud: “I will now start my 60-second timer.”

• Start a 60-second timer.
• Keep your foot firmly on the brake pedal without moving.
  
  

Step 9: Check Air Loss After 60 Seconds

Say out loud: “The 60-second timer is up, the PRIMARY air gauge is at _______, and the SECONDARY air gauge is at ______.”

• After 60 seconds, record the new air pressure readings.
  
  

Step 10: Verify Acceptable Air Loss

Say out loud: “I did not lose more than 4 PSI in a combination vehicle.”

• The vehicle must not lose more than 4 PSI in a combination vehicle.
• If more than 4 PSI is lost, the vehicle fails this part of the test.
  
  

Step 11: Identify Low-Air Warning Light Activation

Say out loud: “I will now fan my service brake until my low air warning light comes on at 55 PSI or ABOVE.”

• Fan the service brake (press and release repeatedly) until the low-air warning light activates.
• The warning light must come on at 55 PSI or above in both the PRIMARY and SECONDARY air gauges.
  
  

Step 12: Record Low-Air Warning PSI

Say out loud: “My low-air warning light came on at ____ PSI on my primary and ____ PSI on my secondary gauge.”

• Record the PSI at which the warning light activates.
  
  

Step 13: Identify Brake Valve Pop-Out Range

Say out loud: “I will continue to fan my service brake until BOTH my brake valves pop out between 20 PSI and 45 PSI.”

• Continue to fan the service brake to further reduce air pressure.
• The tractor and trailer brake valves should pop out automatically between 20-45 PSI.
  
  

Step 14: Record Pop-Out PSI

Say out loud: “The PRIMARY gauge popped out at ____, and the SECONDARY gauge popped out at ____.”

• Record the PSI at which each brake valve popped out.