Start Engine - I will now start the engine. (Start the engine.) The air pressure is building at an acceptable rate. (Wait for normal pressure - at least 100 psi on dual system. Remove your wheel chock while pressure is building. You have just verified that the spring brakes work.)
Parking brake - I am checking the parking brake by pulling out the knob and trying to move the truck. (Pull the parking brake knob out, put the truck in gear, and try to pull gently against it.) Ok, I can tell that the parking brake is working.
Mirrors - I am checking the mirror adjustment.
Pre-trip.net:CDL Pretrip Test Study Guide
Emergency Equipment - I am checking for the required 3 pieces of emergency equipment; an approved fire extinguisher, 3 reflective triangles, and spare fuses. The fire extinguisher should be at least a 5BC. (Fire extinguisher may be in accessable storage area - must have sign on outside saying "Fire Extinguisher Inside")
Clutch, Shifter, Parking Brake - I am checking the clutch (freeplay should be between 1 1/2 and 2 inches), the gearshift is in neutral, and the parking brake is engaged. (Move clutch to check freeplay and move gearshift to make sure it is in neutral; check parking brake button is pulled out.)
Start the Engine.
Gauges - I am checking the gauges. The voltmeter is reading in the correct range. The oil pressure is rising. Temperature is gradually rising as the engine heats up. Air pressure is increasing.
Windshield - (Yeah, you did it during the engine compartment, but you can see it good from inside. You can't check anything too much.) I am checking the windshield for cracks, to see that it is clean, and that it does not have any stickers which are not allowed. I am checking the windshield wipers for missing, damaged, or broken parts; that the rubber is good and it is flat against the windshield.
Wipers - I am checking the windshield wipers for proper operation.. (Turn them on for a couple of wipes.)
With firm pressure on the brake pedal (approximately 90 psi) the vehicle can now lose 4 psi with the brake on. (Wait a few seconds to see how much pressure gauges drop.) It tests OK.
Warning - Now I will test the warning devices. I am fanning the brake pedal to reduce the air pressure. When the pressure drops below 60 psi, a warning device should come on. (Fan till the indicator comes on.) The indicator has come on. It can be a light, buzzer, or wigwag. When the pressure drops into a range of 10 to 45 psi, the tractor protection valve should close and the spring brakes will come on. (Continue fanning until the tractor protection valve pops out.) The tractor protection valve has closed and the spring brakes have been enabled. (You can hear them engage with your door open.)
Wait for normal air pressure and then shut the engine off. Turn the switch back on so that you have electrical power.
Complete brake test - I waited for full air pressure and will now do a brake test. (Push in tractor protection valve and parking brake.) I am pushing in the tractor protection valve and the parking brake. After the initial drop the vehicle can lose 3 psi without any brake pressure applied. (Wait a few seconds to see how much pressure gauges drop. Then press and hold the brake pedal.)
Heater - I am checking the heater and defroster for proper operation. (Turn fan on. feel for output at heater vents and defroster when you move control to those positions.)
Horn - I am checking the city horn and the country horn. (Tap the horn on the steering wheel, and then lightly pull the cord for the air horn.)