CDL Combination Vehicles TestCoupling and UncouplingEasy
What is the primary purpose of the 'dummy couplers' or 'dummy glad hands' found on a tractor or trailer?
- ATo store and protect the glad hands when not in use.
- BTo test the air pressure in the brake lines.
- CTo provide a spare connection point for extra trailers.
- DTo bleed air from the brake system during maintenance.
Show answer & explanationAnswer & explanation
Correct answer: A. To store and protect the glad hands when not in use.
Dummy couplers are used to store glad hands when they are disconnected, protecting them from dirt, moisture, and damage, and preventing air from escaping the tractor's air system.
Why the other options are wrong
- B. Air pressure is tested using gauges or specific test ports, not dummy couplers.
- C. They are for storage, not for connecting additional trailers.
- D. Air is bled using drain valves, not dummy couplers.
Dummy Couplers (Glad Hands)
Storage points on a tractor or trailer for glad hands when not connected, protecting them from damage and preventing air loss.
- Protects glad hands.
- Prevents air system contamination.
- Maintains air pressure in tractor lines.
Memory trick: Dummy for storage, not for air leakage shortage.