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It could be a bad switch in the receiver itself or it needs to be reset. Here are the directions for deactivating and reactivating the system. Try this first.
2003 Ford Mustang V8-4.6L DOHC VIN R
Belt Minder Deactivating/Reactivating
Vehicle Restraints and Safety Systems Seat Belt Systems Service and Repair Procedures Belt Minder Deactivating/Reactivating
BELT MINDER DEACTIVATING/REACTIVATING
Belt Minder Deactivating/Activating
1. Before deactivating/activating the belt minder, set the parking brake.
2. Place the gearshift in P (Park) (automatic transmission) or the neutral position (manual transmission).
3. Place the ignition switch in the OFF position.
4. Close all the vehicle doors.
5. Unbuckle the driver safety belt.
6. Place the parklamps/headlamps switch in the OFF position. (If the vehicle is equipped with Autolamps, this will not affect the procedure.)
1. Turn the ignition switch to the RUN position. (Do not start the engine.)
2. Wait until the safety belt warning lamp turns off. (Approximately one to two minutes)
3. Buckle then unbuckle the safety belt three times, ending with the safety belt unbuckled. This portion of the procedure can be done before or during belt minder warning activation.
NOTE: Steps 3 through 5 must be completed within 60 seconds or the procedure must be repeated.
4. Turn the parklamps/headlamps on then off.
5. Buckle then unbuckle the safety belt three times ending with the safety belt unbuckled. After this step the safety belt warning lamp will be illuminated for three seconds.
6. Within seven seconds of the safety belt warning lamp turning off, buckle then unbuckle the safety belt. This will enable the belt minder if disabled or disable the belt minder if enabled.
7. The following sequence of events confirm the belt minder is enabled:
flashing of the safety belt warning belt lamp four times per second for three seconds
three seconds with the safety belt lamp off
flashing the safety belt lamp four times per second for three seconds again
8. The safety belt lamp flashing four times per second for three seconds provides confirmation that the belt minder is disabled.
9. After confirmation, the deactivation/activation procedure is complete.
Let me know if this helps.
Saturday, August 17th, 2019 AT 5:56 PM