>>dlcarr+3Va
bios flashes are typically preflashed prior to soldering to boards -- some vendors route jtag or spi contacts, but you're more likely to need a vampire/pogo clip on for the TSOP or equivalent chip, or have fun with resoldering the bios flash if you're needing to recover from this.
It's not impossible to do in the field, but you can't really count on vendors surfacing that interface usually.