After we shut off our 98 f-150 we hear a series of 5 beeps with a pause and 5 more beeps. Can anyone tell me what this means?

Thanks

 

To hear this pattern when switching the ignition OFF is quite unusual.

Where is it coming from? Dash on passenger side down behind the glovebox?

Normally, the airbag module sounds this pattern when the instrument cluster AIRBAG light is burned out and there is another fault in the airbag system. Does the AIRBAG light work when the ignition switch is first turned to RUN?

I'd be suspecting several problems at this point.

Steve