Vehicle add-ons sometimes have hidden drawbacks

Vehicle accessories are a billion-dollar business, and that's because relatively few of us are satisfied with the factory equipment our new vehicles come with. Some popular add-ons have hidden drawbacks, and few consumers are aware of them.

Side steps and trailer hitches: These additions can disable hands-free doors and liftgates on a crossover or SUV, or the sliding doors on a minivan, which are activated by kicking your foot under them when your hands are full. They can be rendered inoperative when trailer hitches or running boards block the sensors.

Roof racks: This add-on item may mean the end to silent drives. It may seem obvious immediately afterward, but before they have these installed, few drivers ever think of the wind noise that roofrack crossbars can create.

Front end covers or bras: These are still popular with drivers who want to reduce stone chips on the leading edges of hoods, fenders, and bumper covers. But when installing one, make sure it is compatible with any sensors your vehicle has. There may be sensors in the vehicle's nose to activate forward-collision warning, emergency front braking, park assist, adaptive cruise control, or other features. You need to find out where the sensors are and what type they are.

LED headlight conversion kits: These are quickly becoming as much of a headache for other drivers on the road as those

HID (high-intensity discharge) aftermarket kits, which were outlawed in Ontario in 2017.

The bulbs in these kits may run cool at the shiny end, but they develop a lot of heat at the rear. Manufacturers either install an aluminum heat-dissipating device or small electric fans on the backs of these bulbs to keep things behind the bulbs from melting. The choice is to either run the LEDS without the protection of a weather cover, or stick with the original bulbs.