Electronic box below radio
On my 2001 Insight, the SRS (air bag) control unit is there. If I remember correctly, a new one is not cheap, and please be aware of the warnings about working on SRS equipment to avoid causing danger and expensive damage.
2001 Honda Insight (Blue MT with A/C), ~110,000 miles, ~70 MPG @ 70 MPH, MIMA, turbo
1998 Pontiac Grand AM, ~239,000 miles, ~35 MPG @ 70 MPH, stock
1966 Mooney M20E, ~2,450 hours, ~21 MPG @ 170 MPH, many mods