club.liberty.asn.au

Okay guys I've got a B4 and I've noticed that it has an issue with the brake light when the lights are turned on. It doesn't work with the lights on unless you hit it just right but it works when you have your foot on the pedal. Any help?

Any chance of a better description of the symptoms?
Is it only the driver's side rear brake light that is affected?
Are you referring to the parking/tail lights being turned on?
What is being hit?

Are you saying that the brake lights do not come on when you tap the brakes but come on when the brake pedal is depressed continuously?

A slow responding brake switch would affect both LHA and RHS brake lights.
A faulty earth would affect only one side.
A bad earth on one side may cause the parking/tail light to "fight" against the brake and cause both to die off when both were on.

Get a multimeter and a friend on the brake pedals and confirm.....
(1) that there is 12V appearing at the "hot" side of the bulbs when the brakes and lights are on.
(2) that the earth side of the bulbs never lifts off zero volts when any of the parking/tail lights or brake lights are powered.

It only happens when you turn the park lights on. The brake light doesn't come on with the park lights. It comes on when you put your foot on the brake pedal. What I mean by hit. When you tap the outside of the taillight. It's only affected on the one side which is the drivers side.

Faulty connection somewhere with possibly faulty earth.
Take the light assembly out and clean everything.

That's what I was thinking. And get new globes at the same time.