Seat belt light flashing when ignition turned on

These two faults maybe unconnected. Starting with the seat belt warning. There should be a switch in the seat to check if someone is sitting in it and a switch in the seat belt catch to check if the seat belt is engaged. If either of these switches or the wiring to them is faulty then the light will come on if the ignition switch is turned on. The airbag warning will come on if there is a problem with the explosive that operates the bag or wiring to it. I would check under the front seats of your car for wiring damage or a not fully engaged plug and socket. These can be damaged or work loose if things have been pushed under the seats.

Not surprisingly, many others have experienced problems with the ignition switch on this car. Historically, it is not a sound, but that the key is stuck in the ignition. http://repairpal.com/key-will-not-come-out-of-ignition-570 Your problem sounds different, but it may be related. Although I do not recommend the fix in the link above, it is possible the previous owner of your car did perform this fix and it has resulted in the problem you now have. My better guess is that the chime/buzzer has failed due to moisture or dirt and is no longer producing the sound that it should, but instead is altered to the ringing you describe.To disable follow these instructions:

1. Turn the ignition switch to the RUN (or ON) position. (DO NOT
START THE ENGINE)
2. Wait until the safety belt warning light turns off. (Approximately 1
minute)
Step 3 must be completed within 50 seconds after the safety belt
warning light turns off.
3. For the seating position being disabled, at a moderate speed, buckle
then unbuckle the safety belt 9 times, ending in the unbuckled state.
(Step 3 must be completed within 50 seconds after the safety belt
warning light turns off.)
After Step 3, the safety belt warning light will be turned on for three
seconds.
4. Within 10 seconds of the light turning on, at a moderate speed, buckle
then unbuckle the safety belt.
This will disable the BeltMinder feature for that seating position if it
is currently enabled. As confirmation, the safety belt warning light will
flash 4 times per second for 3 seconds.
This will enable the BeltMinder feature for that seating position if it
is currently disabled. As confirmation, the safety belt warning light will
flash 4 times per second for 3 seconds, followed by 3 seconds with the
light off, then followed by the safety belt warning light flashing 4 times
per second for 3 seconds again.
I hope this helps. Good luck.

don't worry be happy . start to worry when it causes you a problem

U HAVE ACTIVATED SPEED WARNING!!USE MANUAL TO DEACTIVATE!!

You will need to replace the ignition starter switch, this switch is operated by a long steel rod from the ignition key cylinder, it is located under the dash on the top of the steering column tube, it has a very large connector going to it. See the photo below of the part.
Color of switch is black .

MOTORCRAFT Part # SW5011 {#F4DZ11572B} $18.96

check and see if there's any other icons flashing on the dash other then the warning lights. it may also be that the warning light has blown or someone removed it so they could sell it. other then that all you can really do is check the book that came with the car for reasons that there's a warning beep or take it to a mechanic that has a scan tool with the software for that specific vehicle.

Hope this helps ya.. Cobra.. :-)

Belt-Minder® Deactivating/Activating Vehicles Built After 5/27/03
Preparation

1. Before deactivating/activating the belt minder, set the parking brake.

1. Place the transmission range selector lever in PARK.

1. Place the ignition switch in the OFF position.

1. Close all the vehicle doors.

1. Unbuckle the driver and passenger safety belts.

Deactivating/Activating

1. Turn the ignition switch to the RUN position. (Do not start the engine.)

1. Wait until the safety belt warning lamp turns off (approximately 1 minute).

1. NOTE: Step 3 must be completed within 50 seconds after the safety belt warning lamp turns off or the procedure must be repeated.
   For the seating position being disabled, buckle then unbuckle the safety belt 9 times, ending with the safety belt unbuckled.

1. NOTE: After Step 3, the restraint system warning indicator lamp turns on for 3 seconds.
   Within 10 seconds of the safety belt warning indicator turning on, buckle then unbuckle the safety belt.

1. The beltminder activation or deactivation is confirmed by the following sequences:
   • If the beltminder is enabled, this procedure will disable the beltminder for that specific seating position. The safety belt warning indicator lamp will flash 4 times per second for 3 seconds to confirm that the deactivation procedure was successful.
   • If the beltminder is disabled, this procedure will enable the beltminder for the specific seating postion. The safety belt warning indicator lamp will flash 4 times per second for 3 seconds followed by a second series of 4 flashes per second for 3 seconds to confirm that the activation procedure was successful.

1. After confirmation, the deactivation/activation procedure is complete.

Vehicles Built Prior To 5/27/03
Preparation

1. Before deactivating/activating the belt minder, set the parking brake.

1. Place gearshift in P (Park) (automatic transmission) or the neutral position (manual transmission).

1. Place the ignition switch in the OFF position.

1. Close all the vehicle doors.

1. Unbuckle the driver safety belt.

1. Place the parklamps/headlamps switch in the OFF position. (if vehicle is equipped with Autolamps, this will not affect the procedure.)

Deactivating/Activating

1. Turn the ignition switch to the RUN position (Do not start the engine.)

1. Wait until the safety belt warning lamp turns off (approximately 1 to 2 minutes).

1. NOTE: Steps 3 through 5 must be completed within 60 seconds or the procedure must be repeated.
   Buckle then unbuckle the safety belt 3 times, ending with the safety belt unbuckled. This portion of the procedure can be done before or during belt minder warning activation.

1. Turn the parklamps/headlamps on then off.

1. Buckle then unbuckle the safety belt 3 times ending with the safety belt unbuckled. After this step the safety belt warning lamp will be illuminated for 3 seconds.

1. Within 7 seconds of the safety belt warning lamp turning off, buckle then unbuckle the safety belt. This will enable the belt minder if disabled and disable the belt minder if enabled.

1. The following sequence of events confirm the belt mnider is enabled:
   • flashing of the safety belt warning belt lamp 4 times per second for 3 seconds
   • 3 seconds with the safety belt lamp off
   • flashing the safety belt lamp 4 times per second for 3 seconds again

1. The safety belt lamp flashing 4 times per second for 3 seconds provides confirmation of belt minder disabled.

1. After confirmation, the deactivation/activation procedure is complete.

flashing dashboard lights when the ignition is turned off

From the F-150 Forums, since I just bought one and this worked!

This is straight from my 2009 f150 owners guide

Preperation
1. the parking brake is set
2. truck in park
3. ignition switch is in off position
4. both seat belts are unbuckled

Disable Belt-Minder
1. turn the ignition switch to the on position, DO NOT START THE ENGINE.
2. wait until the safety belt warning light turns off. (approximately 1 minute).
* step 3 must be completed within 50 secs after the safety belt warning light turns off.
3. buckle then unbuckle the seat belt nine times, ending in the seat belt unbuckled.
* after step 3 the restraint warning light, (airbag light) will turn on for three (3) seconds.
4. within approximately seven (7) seconds of the light turning off, buckle then unbuckle the safety belt.
* the restraint system warning light will flash four, (4) times per second for 3 seconds for confirmation

you can do this for the passenger side also!!!


*NOTE
in step 3. after three times buckling and unbuckling the restraint warning light lit up in my truck. SO I WENT TO THE NEXT STEP, (STEP 4). waited 3 seconds and i buckled and unbuckled.

in the buckle /unbuckle procedure do it some what slowly and watch for the light. it may not take 9 times.
__________________

Wear your safety belt, or simply unplug the harness located at the seatbelt receptacle.