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Sometimes drivers side brake light dosent work

my drivers side brake light wont work until i turn on the turn signal and turn on the parking light then it works. i have changed the bulb and the socket…what the heck?

Try changing the bulb.

And also inspect the socket and electrical leads. They can become rusted or fouled from dampness leaking in around the lamp assembly.

as i said…i put in new bulbs

new socket also

I think you’re going to have to start testing the wiring. You’ve eliminated the bulb and the socket, there isn’t much left.

i know youre not going to like this. (and some others on here may say im quacky too) but change ALL the lightbulbs. left rear, right rear all bulbs. stop, turn, tail.

sometimes ONE bulb either out or corroded can make the others act wacky. what model, year and car. more info helps out.

also the blinker flasher relay may need repalcing.

although this sounds like overkill, these items probably only total 15 or 20 bucks.

try them, it would be cheaper than paying shop diagnostic fees.

I have to admit I wouldn’t have thought of this, but after reading cappy208’s post I think it’s good advice and certainly worth a try.

also, check the hi brake light. those can also effect the rest of the lights.

i mentioned giving the make and model. this is because some cars control each light bulb via the computer. not only which bulb, but the intensity, and timing of them too. really… more info is better. it helps everyone give pertinent info to your specific case.

The brake light circuit runs through the turn signal switch circuit. I have seen the turn signal switch cause this kind of thing because the switch contacts were not making contact correctly in the switch. You might try moving the turn signal switch lever around while the brake is on and see if that makes it work. The flasher unit may be the cause also, as was mentioned.

When I had an intermittent tail light and changing the bulb made no difference I finally discovered that the fuse and its receptacle had a little corrosion buildup. I cleaned the receptacle with emery cloth and cleaned the fuse on a rag then sprayed both with WD-40 to kill the corrosion. It did the trick.