CDL BRAKE TEST
(This is the verbiage of what needs to be said/included.)
“I am going to perform a safe start.” Depress clutch. Place the gearshift in neutral. Start the engine then slowly release the clutch. (Ignore clutch section if automatic)
“At this time I will release the trailer and tractor brakes by pushing in the tractor protection valve and the parking brake valve.”
“Now I am going to help the air system build pressure by stepping on the gas pedal. The governor cuts in at 100 psi and cuts out at 115 psi at which point the air system is fully-charged with a purge.” *(Purge) There’s the purge. “The air supply pressure gauge primary and secondary needles are reading at 115 psi indicating the air system is fully-charged.” (psi may vary on truck)
“I will now turn off the vehicle, let the motor die completely and then turn the key back on to ACC mode.”
“First test I’m going to perform is the Applied Pressure test. For this test I will fully apply the foot brake for 1 minute. After the initial loss I should not lose more than 3 psi (Class B) or 4 psi (Class A) within that minute.” *(Fully apply the foot brake then give primary and secondary reading.)
“After initial loss, the primary and secondary needles are reading at 100 psi. I will begin the minute now.” *(Start timer) (psi may vary on truck)
“The minute is up, the primary and secondary needles are still reading at 100 psi indicating the system had no air loss, is working properly and is in operational range. That completes the Applied Pressure test.” *(Take foot off brake)
“Next test I’m going to perform will be the Low Air Warning Light and Buzzer test. For this test I will fan off air pressure by rapidly applying and releasing the foot brake. The low air warning light and buzzer should come on before 60 psi. I will begin fanning now.”
*(Fan Service Brake)
“There’s the Low Air Warning Light and Buzzer. The primary and secondary needles are reading at ______ psi indicating that they are working properly and it is in operational range. That completes the Low Air Warning and Buzzer test.”
“At this time I will turn the truck completely off.”
“Next test I’m going to perform will be the Tractor and Trailer Emergency Automatic Spring Brake test. For this test I will continue to fan off air pressure. Between 20 and 40 psi on the tractor-trailer combination vehicle, the tractor protection valve and parking brake valve should pop out. I will continue fanning.” *(Continue fanning the Brakes)
“The tractor protection valve and parking brake valve both popped out. The primary and secondary needles are reading _____ psi indicating that they are working properly and in operational range. That completes the tractor and trailer emergency automatic spring brake test.”
“I will now exit the vehicle to grab the chocks.” *(Grab key and exit facing the vehicle using 3 points of contact. Grab chocks and re-enter using the proper 3 points of contact.)
“I am going to perform a safe start.” Depress clutch . Place the gearshift in neutral. Start the engine then slowly release the clutch.
“I am going to help the air system build pressure by stepping on the gas pedal. The governor cuts in at 100 psi and cuts out at 115 psi at which point the air system is fully-charged with a purge.” *(Purge) “There’s the purge. The air supply pressure gauge primary and secondary needles are reading at 115 psi indicating the air system is fully-charged.” (psi may vary on truck)
“Next test I am going to perform is the tractor and trailer tug test. For this test I will push in the parking brake valve, releasing the tractor brakes to test the trailer brakes by putting the gearshift in first gear and slowly releasing the clutch until I feel a tug.” *(Pull Forward)
“There’s the tug indicating the trailer brakes are working properly and in operational range. I will place the gearshift back in neutral.”
“Next I will pull out my parking brake valve and push in the tractor protection valve, releasing the trailer brakes to test the tractor brakes by putting the gearshift in first gear and slowly releasing the clutch until I feel a tug.”
“There’s the tug indicating the tractor brakes are working properly and is in operational range. I will place the gearshift back in neutral. That completes the Tug test.”
“The final test I will perform is the Service Brake test. For this test I will release the tractor and trailer brakes, place the gearshift in first gear, move the vehicle forward about 5 mph and apply the brakes firmly using the brake pedal.”
Things to look for:
“This test may show problems which you otherwise wouldn’t know about until you needed the brakes on the road.”
“The vehicle didn’t pull to any side, no unusual feel or delayed stopping action indicating it works properly and is in operational range. If it did, it could be because of low air pressure, a suspension issue or any number of brake problems such as slack adjuster out of adjustment, excessively worn brake pad or even a loose brake drum. That completes the Service Brake test.”