I have 2010 Ford Fusion, there is weird sound coming from inside the dash when I turn the key on and then goes back off, then in about 1 minute the sound come back on and stays on until the key is off

SOURCE: Seat belt warning light on. 01 VW Golf

More likely to be a sensor - check gsf (google it - german, sweedish, french car parts) for the seat belt sensor

SOURCE: Ignition turns and key warning light comes on. Its a 98 Ford Expl

Sounds Like the Starter RELAY is Bad After Exhausting All other Test, Go For The RELAY
A SURE-SHOT way Is to Jumper Wire From Battery to (STARTER SIDE) of Relay if starter Works then Its the Starter Relay if NOT>>Then Its the STARTER<) Relay Instruction Below. STARTER Instructions Very Bottom
REMOVAL
WARNING: WHEN PERFORMING MAINTENANCE ON THE STARTING SYSTEM BE AWARE THAT HEAVY GAUGE LEADS ARE CONNECTED DIRECTLY TO THE BATTERY. MAKE SURE PROTECTIVE CAPS ARE IN PLACE.

1. Disconnect the battery ground cable.
   1. Disconnect the starter motor solenoid relay switch wiring.
   1. Remove the protective cover.
   2. Disconnect the push-on electrical connector.
   3. Remove the nuts.
   4. Remove the cable.
      1. Remove the starter motor solenoid relay switch.
      1. Remove the engine sensor/generator wires.
      2. Remove the bolts and ground wire.
      3. Remove the starter motor solenoid relay switch.
      INSTALLATION
      
   5. Follow the removal procedure in reverse order NOTE: When the battery is disconnected and reconnected, some abnormal drive symptoms may occur while the vehicle relearns its adaptive strategy. The vehicle may need to be driven 16 km (10 miles) or more to relearn the strategy.

1. Disconnect the battery ground cable.
2. Raise and support the vehicle.
3. Remove the starter motor solenoid terminal cover.
   1. Disconnect the starter wires.
   1. Remove the nuts.
   2. Disconnect the wires.Remove the nut and the starter ground cable
   3. Remove the bolt and the starter motor.
      1. Follow the removal procedure in reverse order. NOTE: When the battery is disconnected and reconnected, some abnormal drive symptoms may occur while the vehicle relearns its adaptive strategy. The vehicle may need to be driven 16 km (10 miles) or more to relearn the strategy.
      
      

SOURCE: seat belt alarm goes off when belt is buckled

try relapsing the switch inside the female of the seat belt

SOURCE: 19995 Ford Ranger seat belt won's stay latched

Your best bet is to replace it. My thought is if it deals with safety, its best to just replace the bad or failed part.

SOURCE: Driver Heated Seat 03 Suburban

Identical thing here with my '03 Surburban LT.