Horn/Security going off randomly

[2006Overlander]

2006 Expedition EB 5.4 bone stock besides independently wired ditch lights and air horn

Recently while at school or at work, cars parked beside me will trigger the locking feedback horn and light flash. If the car is barely tapped it will do the same. It will also sometimes trigger as what I believe is an alarm response but the horn and lights are not flashing in sequence or in the panic mode "pattern". I have checked all fuses and relays that I can think of and all are intact and not burnt. I am completely lost as to what to do as the Facebook group is absolutely no help at all. I have disconnected the horns as quick fix for now so the horn isn't stuck on. But the lights will still flash.

 

[whtbronco]

Any DTC's show up on diag scan? That needs to be the first step in your quest I think.

If I had to guess I'd say the Vehicle Security Module is faulty. Assuming it's in the same location as my '04 model since both are Gen2 it's on the passenger side up front.

 

[2006Overlander]

Any DTC's show up on diag scan? That needs to be the first step in your quest I think.

If I had to guess I'd say the Vehicle Security Module is faulty. Assuming it's in the same location as my '04 model since both are Gen2 it's on the passenger side up front.
View attachment 75888

Thank you. I don’t have a sophisticated scanner. No DTCs as of now.

 

[whtbronco]

Not sure if codes for the VSM will show up, but most of the big auto parts chains will run a diag scan for free, but they use a fairly basic OBDII scanner around here at least.