Main lughts come on when press brake.

miggiwoo

I have a Chevrolet Matiz and had to replace the brake light bulb the other day.Did it without any problems and the brake light works fine.
Next day my wife came home and said that when she pressed the brake the main lights came on ( during the day).I checked it and was the same for me.When you drive at in the dark with the main lights switched on everything is fine and works as normal.
Is it just a coincidence and just a wire that has been crossed/moved ?

Thanks :money:

Hintza

Sounds like time for an auto electrician.

First thing though, just go back to the bulb you changed and check all is ok (no wires/connections touching etc ).

ianders

Bulb has been put in wrong by the sounds of it. Is it a regular incandescent or some other style of bulb? Try taking it out, rotating it 180 degrees and putting it back in (incandescent won't make a difference).

If it's not that, it will likely be an earth issue. Did you have to unscrew the rear cluster to access the brake lights? Is the screw nipped up providing good body contact?

scotsbob

Once you have checked it taken it to garage and got an auto electrician, come back and tell us how many it took to change a light bulb.

AnnieO1234

I had this with a fusion, didn't bother to look properly and replaced a double filament brake light bulb with a single. Did exactly the same, flashed the headlights when hitting brake.

If you don't have the broken bulb, check the other side, take the faulty bulb out and buy a new one.

Xx

poppasmurf_bewdley

I had a similar problem years ago when replacing a brake/side light bulb. The filaments were touching each other so when I pressed the brake, the side lights came on. And when I switched on the side lights, the brake lights came on.

Another problem I had was on an automatic Ford. When I engaged drive, the headlights came on. I found that a wire going to the headlights was routed near the auto shift and the wire became trapped and when placed in drive it earthed and caused a circuit.

molerat

My money is on either
Twin filament bulb replaced with single
or
Bad earth.

miggiwoo

Sorted it.I had put the wrong bulb in , although they did look very similar.
Just swapped the bulb over again and , hey presto , no main lights when I press the brake.
Thanks very much for the replies , much appreciated.