No interneta dzīlēm var redzēt ka dublēja noteikumu dēļ. Kāds jums ir defekts jāprasa tomēr autoelektriķim.

If you've ever spent some time following an Audi Q5 or Q7 in heavy traffic, and you were bored with little else to do, you may have noticed something: Audi's SUVs have two sets of brake lights. Only one of them actually turns on, in normal driving, but the other set is there, just waiting for its chance to dazzle the world with its illumination.

Here's why.

For several years -- maybe decades, who knows? -- the federal government has had a regulation that no headlights or brake lights can be on a movable piece of automotive bodywork. So if it moves, it can't include a brake light or a headlight. That means a car company can't stick its headlights on a car's hood, and it can't stick its brake lights on a car's tailgate, because those items could be open while you're driving, potentially rendering it impossible to see your headlights or brake lights.

Audi, no doubt well-aware of this regulation, went ahead and designed the Q5 and the Q7 with the brake lights on the tailgate.

Now, I know what you're thinking. This is a no-no. This shouldn't be allowed. THEY CAN'T GET AWAY WITH THIS!!! And indeed, they didn't. In order to meet the requirements of the regulation, Audi also installed a second set of brake lights on the Q5 and the Q7.

So here's what happens. In normal driving, when you're just cruising around in your Q5 or Q7, the brake lights on the tailgate are operational. But the moment the vehicle detects that the tailgate is open, those brake lights cease to function. When that happens, the second set of brake lights -- located in the bumper -- immediately take over, providing the functions of brake lights, taillights, turn signals and even reverse lights. Then, when the tailgate is shut again, it's back to the regular old brake lights in the tailgate.

Since Audi figured out this workaround, several other automakers have used the idea. The Lincoln MKC and MKX crossovers now also employ a second set of brake lights in addition to their standard tailgate-mounted set, which work exactly the same way as the lights in the Q5 and the Q7. It's the same story with the brake lights on the new Mini Clubman: They're mounted on the car's rear doors, with a second set in the bumpers in case the doors are opened.

So now, the next time you're in traffic behind an Audi Q5 or Q7, you won't have to wonder why it appears to have two sets of brake lights. This will leave you with ample time to ponder other things, such as how cool it would be to have headlights mounted on your hood so you can shine lights into third-floor windows and annoy your friends. We can dream.