lots of electrical issues and a little help on where to start.

[Jaegze]

2008 3.0si

When I first got the vehicle the fog lights would flicker and one is on all the time but they both work when I put on the switch.

Everything else worked as normal.

Fast forward two years and this is where I am at.

SOS error, rear parking sensor error, loss of aux output on radio, loss of phone on radio. The car started slow a few times over the winter but it was cold so i did not think much of it. Also I did not know that lcd fog lights may cause the flickering and some of the issues with those, so I am going to check if they were coded or just put in there when I get a chance to sit down and figure it out.

Checking the numbers on the dash, the car runs at close to 14.9 volts. When i hit the brakes coming to a stop it drops to around 12. When the car sits for more than a few hours it drops to around 11 but has been starting easily.

Yesterday, the right rear brake light stopped working. I took the bulbs out to check them and nothing cleaned/checked all the connectors and still no taillight brake light and now nothing to the right rear lighting. I checked bubs etc with the other side and all those are ok.

I dont know the history on the battery and feel I should just replace it at this point since im having these issues and the volts seem low when it sits.

I am new to inpa and will get ncs expert but dont have the experience to really get into them to break this all down.

Hopefully this makes sense, if not please ask. Again, I dont know where to start and I think I should replace the battery and go from there. TIA