I have a mazda 3 hatchback sport 2004, and it's got a very strange issue: the tail light on the passenger side works fine when I start the first time, but as soon as I press the brake and release it, the LED lights switch off. Pressing and releasing the brake again doesn't do the trick. However, after resetting the lights (either by switching the engine off and on again, or after unplugging the light wires and plugging them back in) the LEDs work again until, of course, I press the brake again!

I've been told to change the tail lights as it's an intermittent issue, but is there anything I can try before committing to pay for a pair of lights?

thanks in advance for your help!

 

I have exactly the same issue
Did you ever get this sorted?

 

Unfortunately I cannot remember to be honest. I didn't have the car for a lot longer after my post so cannot remember what I did with it.

 

Tail light stops working after brake - works again after reset

There is an old post out there about this issue. And even more when you search the open web.
I have just got mine fixed. Was not a relay problem and although the diagnosis was not pointing to the tail light itself - replacing it fixed the problem.
It seems there is some complexity in the circuit board inside the tail light that somehow results in one circuit cutting out when the other is triggered.
If anybody else is interested (has the same problem), I have kept the old unit and could pull it apart to determine what exactly has "blown" (it is not the LED's - they still function independently)

 

Update - I have pulled the old tail light apart and fixed it. The problem was dry solder joints in the circuit board - one of the 4 pins that is soldered onto the board to carry the signals through the plastic to the LED arrays.
Dismantling is relatively easy - hot air gun around the joint and pry it apart.
Pity I had to buy a new (reused) fitting before I could pull it apart - but that's cool - listed at ten bucks on local auction site in case it can help someone else out. It seems it is a common fault because all of the auto dismantlers sell them as the wrecks come in - and it is always the left side - there are plenty of RH side fittings available.
Perhaps a production line issue - the person assembling the left hand fitting is unskilled?