Brake lights on my car turn on when the car is turned off

ALISON RIBBONS

MEMBER
1999 NISSAN ALTIMA
AUTOMATIC
160,000 MILES

Sometimes they turn on overnight and stay on all night. If I notice them on and pump the brake, they will go off. I have replaced the brake light switch twice to be sure that's not it. It didn't make one bit of difference either time.

The brake lights on both sides as well as the upper brake light that is inside the car all turn on. Could this be fuses or something else?

This brake light issue drains the battery so my battery is constantly draining. I've been jump starting it in order to drive the car. It always starts but I have to jump it every time I drive, regardless of how long the car has been running.

How can I fix this issue? Or at least diagnose it?

1 Reply

CJ MEDEVAC

MECHANIC
11,004 POSTS

ALISON RIBBONS,

I just looked over the wire diagram for your rig.

From the fuse to the pedal switch to the brake lights.

Nothing else in between.

Your switch works just like the one in my Jeep CJ-5.

When installed correctly, the plunger is fully pushed inside the switch's housing when the brake pedal is in it's static position.

Pushing the pedal slightly immediately lets the plunger out and the brake lights come on, the plunger remains out as the pedal is pushed further towards the floor.

Back to my Jeep CJ-5, my switch housing is made of plastic and is threaded like yours. In the past, the plastic threads stripped or the switches holder stripped. End result: the switch moved back in the holder and the plunger was out with the pedal in the static position, my brake lights remained on.

On yours, things to check.

Is the plunger all the way in with the pedal up?

Is the lock nut tight, keeping the switch in place?

Can you tell if the holder is stripped?

Is the plunger lining up with the plate on the pedal well? Not bent.

Lastly,

Maybe your pedal is stubborn, maybe it does not fully come to the top each and every time it is released.

If that may be the case, see if you can oil the pivots well (even the spring tips where they connect to the pedal) so that the pedal will move freely.

Picture 1) Your switch

Picture 2) My Jeep switch

Return with good news!

The Medic

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