Buzzing Under Steering Column??

After 14 months of no mustang, I finally got my build to a point where I could turn the ignition to the "on" position to start testing my fuel pump pressure (and then maybe the car) but soon as I put the key in the ignition switch I am greeted with this buzzing noise that is coming from under the steering column in the fuse box area. I didn't have the air bag on at first, so i thought maybe it was a safety thing where I had to reconnect the airbag but that didn't help. I have never heard a mustang make a noise like this before, it actually sounds like a buzzer. It does not go away if I turn the key to the on position either. I do not want to turn over the motor yet until I know my fuel pressure is correct so I haven't tried the start position. Anyone experience this before?

Thanks!

I've been doing some digging with very little success except for this little bit of info from someones build log:

Went to start the car and hit 2 problems
The constant control relay module was buzzing, thanks to some help from a local ford guy I found out it only buzzes when it is not grounded properly so we knew we had a break somewhere in the wire, instead of taking days to find that wire we just tapped it near the relay box and grounded it to the body directly got instant power , tested for spark and tested to see if fuel pump was priming , then final test was fuel pressure.

Click to expand...

Sounds very much like what I am experiencing. I will need to figure out where the ground should be or a way to test if it is open.

Thanks- yea lol forgot thats mounted on the coolant overflow tank! Duh! Found a loose ground by it anyway.. still didn't solve the buzzing. At least I have fuel pressure!

The steering column is locked from letting me start the engine. The only thing I can spot under the steering column is a couple connectors open- one is a 2 pin connector with green + white and black sitting by itself. This used to be an auto, I wonder if this was the shift lock connector.. I can't remember I pulled it out well over a year ago, no more shift lock. The other is a 3 pin connector with purple and orange, black and I think orange and green? It comes off the harness going into the airbag control box. It doesn't look like its ever been plugged in before, and I don't see anywhere it could possibly go. I will have to find some wire diagrams

Ryan

FIXED!

Fixed this problem tonight. I ended up pulling off the steering column to fix my ignition switch problem (key wouldn't turn to start position, it was just out of sync mechanically) and I decided since I had the ignition switch disconnected and the other harnesses it would be a good time to test hooking up the battery. When I hooked it up, the buzzing noise was not there. So then I put in the larger harness connector (the one with 16 wires) and the buzzing returned! So that started to narrow it down. I then went to the fuse block and started pulling fuses one by one until I reached #9 which is the brake switch. After #9 was pulled, the buzzing stopped!

So then I remembered, I never put back in my tail light harness! I quickly put in the tail lights and harness, put back the #9 fuse and no more buzzing. It turns out, my hazzard switch was ON, which explains the steering column connector. I guess the buzzer is a way to let the driver know their brake lights do not work, very interesting, never knew that was there.

Can't wait to try and start the car tomorrow to find the next problem!

Ryan