Trouble With The Brake/Shift Interlock Relay Switch.

[FlaAveo5]

Hey guy: It is the switch/relay that is under the dash, behind the brake pedal. I have replaced next to all the rear light bulbs a few months ago, nearly all of them went bad one after another, as i replaced one, another blew out...I think i replaced 3 of the 4 bulbs?

I never would have thought that the rear lights would have anything to do with the relay switch. But they all work now, and have not blown out since replacing them, they were all old. And that was months ago, (and about 3 relay switches ago). The relay is now working fine...again! I had to move my car for this storm, and it 'clicked' as usual as i stepped on the brake. No problem. So now it is working again! IF it matters. It SEEMS to make a much louder 'click' sound when I step on the brake pedal, meaning I can hear that it IS working, it is unlocking the 'brake/shift lock'....it seems to get louder each time they change it, and I can feel the 'click' in the shifter itself, with my hand on it, as i push on the brake.

I recall it being much more of a quite/gentle 'clicking' sound, over the years, when it lasted with no problems for 9 years? But for the past 3-4 replacements, you can hear and feel that relay switch being activated when i step on the brake pedal. It use to be VERY quite,now it is very loud. I thought they finally made one that would last years again,but maybe it is getting a ton of power, and it is making it loud???
I even pointed this out to my Chevy service writer, the same guy I have seen for 11 years now, amazing!, (same guy), that... 'i can hear and feel the relay working as i step on the brake, and then the next time i get in the car, minutes later, it isnt working!'

He never says anything about it being loud being a problem. Just that it obviously needs a 'diagnosis' to find out why it keeps blowing out. I know it needs it to, but i was hoping that maybe, someone, especially YOU, might have the answer, or have encountered this problem before. I check the rear lights frequently, to be sure they all work...I dont want a ticket. I only have to replace the damn headlight bulbs...'Silverstars' frequently, and this set is now a year old. I REALLY dont drive at night almost at all. so they are lasting this time! But they burn out fast. So it could be a short in a rear bulb connection? I just look for rusty wires?

There is a fuse/relay in the fuse box in the engine compartment? Is it labeled 'brake' or Shifter, or what? Do you know? Thanks Sorry...which side is this ground wire in the back? and is it under the carpet back there, or along the rear wall or where? Is it a wire screwed down to the floor? Or something more 'complicated'