In my 2007 Hyundai Accent, the seat belt light won't stop flashing and alarm won't stop ringing even when seat belt is buckled.

Here is a video how to disable it.

https://www.google.com/search?q=2007+Honda+CRV+seat+belt+alarm+that+won%27t+stop

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Belinda, could be a bad wire,plug,seat belt switch/sensor. Have a good tech. diagnose and estimate repair. Check the attached links,instruction and guides, Good luck
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Seat Belt And Battery Lights Flashing
Driver Side Seat Belt Buckle Open short
Hyundai Seat Belts Repair Replacement

Its a 2015, take it back to the dealer. Sounds like a bad sensor.

YOU CAN' DISABLE THE ALARM.IS PART OF SRS SYSTEM.BUY FROM YOU LOCAL DEALER BELT BUKAL ONLY AND REPLACE.IS EASY AND LOW COST.

Have the same problem in my 98 Toyota Rav4. I squirted the female buckle (bolted to seat, not holding strap harness) with wannabe WD-40 lubricant from the $1 store, and it seem to have solved the problem. I'm guessing the spring mechanism is worn out, which is why the harness buckle won't lock. Another solution is to replace the female lock buckle with an identical part from the used parts junkyard store.

The seatbelt light on the dash stays "on," even when everyone has their belt on, but I don't bother servicing that. If yours have an audible alarm instead of an indicator light on the dash, locate the source of the alarm sound and disconnect the wires to silence the sound.

check at the base of the buckle where it meets the floor and check the electrical connector there is a switch inside the buckle also check to see if the wire has rubbed against the track

Find and disconnect the seat belt buckle connector. short the two wires together on the harness side with a paper clip. If the chime/buzzer quits, the problem is in the buckle assembly. If the chime/buzzer is still going off, the problem is some where in the wiring or module.

The relay is located under the divers side instrument panel. You will find it easy enough since it chimes all the time with the key on
Here is a website for a free owners manual too if needed

http://pdfservicemanual.com/automotive/2004-hyundai-accent-owners-manual

It might be the seat belt receptacle.

2003 HYUNDAI TIBURON Recall ID from NHTSA: 02V290000 Auto Recall Date: NOV 05, 2002 Vehicle Component: SEAT BELTS:FRONT:BUCKLE ASSEMBLY Model Affected TIBURON Estimated Vehicles Affected: 7382 Recall Details Auto Recall Date: NOV 05, 2002

Vehicle Component: SEAT BELTS:FRONT:BUCKLE ASSEMBLY Estimated Vehicles Affected: 7382 Model Affected2003 HYUNDAI TIBURON

2003 Hyundai Tiburon Defect Summary:ON CERTAIN PASSENGER VEHICLES, THE DRIVER SEAT BELT BUCKLE WIRING COULD BE DAMAGED BY INTERFERENCE WITH THE DRIVER SEAT CUSHION HEIGHT ADJUSTER MECHANISM.

Defect Consequence:DAMAGED DRIVER SEAT BELT BUCKLE WIRING COULD CAUSE THE SEAT BELT WARNING LAMP OR THE SUPPLEMENTAL RESTRAINT SYSTEM (SRS) AIR BAG WIRING LAMP TO ILLUMINATE. IT COULD ALSO CAUSE THE AIR BAG FUSE (CAVITY NUMBER 5) TO OPEN, PREVENTING AIR BAG DEPLOYMENT. NONDEPLOYMENT OF AN SRS AIR BAG IN A CRASH WHERE AIR BAG DEPLOYMENT IS WARRANTED COULD INCREASE THE RISK OR SEVERITY OF INJURY IN A CRASH.

Remedy:DEALERS WILL INSTALL A NEW DRIVER SEAT BELT BUCKLE, IF NECESSARY, AND WILL PLACE A PROTECTIVE COVER OVER THE DRIVER SEAT BELT BUCKLE WIRING TO PREVENT DAMAGE FROM OCCURRING. OWNER NOTIFICATION BEGAN ON MARCH 24, 2003. OWNERS WHO TAKE THEIR VEHICLES TO AN AUTHORIZED DEALER ON AN AGREED UPON SERVICE DATE AND DO NOT RECEIVE THE FREE REMEDY WITHIN A REASONABLE TIME SHOULD CONTACT HYUNDAI AT 1-800-633-5151.

Estimated Vehicles Affected: 7382

Notes: HYUNDAI MOTOR COMPANY 056