Why do we manufacture stop light switch kits?
For your peace of mind — ROADMASTER taps into the brake light switch so the motorhome monitor activates only when the brake pedal is depressed. Other manufacturers have monitors that only indicate that the air cylinder is extended. If these other systems are incorrectly positioned with the brake pedal depressed, the driver of the motorhome will not be alerted that the brakes are being damaged or destroyed.
With a ROADMASTER system, you ALWAYS know when the brake pedal is depressed — avoiding expensive and unnecessary damage to your towed vehicle’s braking system.

How can you tell if you need one?
If the brake lights do not work with the towed vehicle’s ignition key turned to the “tow” position, you need a stop light switch kit to make your vehicle legal to tow.