I've got an electronic buzzing noise?

[70 FJ40]

My Cruiser started buzzing today right after starting it. The buzzing starts right after the seat belt/door finger stops. It's kind of a high pitched continuous whining or buzzing. Definitely electrical. Checked all the doors to make sure they were closed, clicked the seat belts too. Nothing seems to make a difference. Anyone else experienced this? Where should I start looking? It's an '01 with 130k. I did install new wiring for a fridge in the back a few months ago. I put it on its own fuse block right off the battery. And the battery is only a couple months old as well.

 

[n55luvr]

Hopefully not brake warning buzzer. Might indicate issue with master cylinder / abs system.

 

[70 FJ40]

The brake light was not on so I don't think that's it. I don't know though.

 

[Trunk Monkey]

Isolate where it's coming from. Try disconnecting your new wiring at the battery to see if that's the cause. Is it HVAC fan related?

 

[70 FJ40]

Well I don't know where it was coming from. But I got it to stop. A few months back I did that mod in the relay box where you take out the relay for the 12v plugs and put in a jumper wire so they are always hot. This mod has caused some funny issues before like my truck not running well and even not starting. I thought that would be the easiest place to start so I put the relay back in and the whining noise stopped. So there can definitely be negative side effects from doing the 12v plug mod.