'2007 mazda 6 2.3 manual shift Keeps blowing the fuse for the taights
Why does my Taillights fuse keeps blowing
The simple answer is:
"because the circuit is drawing more current than the rating on the fuse".
But I suspect that is not really your question. The reason question is WHY is the taillight circuit drawing more current than it's supposed to?
Check the following:
Be sure you have the CORRECT specification bulbs in all the sockets on that circuit. Some bulbs have a greater current draw than others and using the wrong bulbs can cause this. Check your owners manual or service information for the correct bulb types.
Check for wiring faults. This is especially the case if modifications, like trailer wiring, have been made. It's easy for a short circuit to develop. Also check for rodent damage. Some wires are attractive to mice and other rodents and they will chew through the wires leaving you with an easy-to-short situation.
Check that there is no damage to any of the bulb sockets on the circuit. Sometimes bad connections due to corrosion can lead to hot spots which can melt parts of the bulb socket and lead to shorts.
If you don't have a multimeter, it's time to get one as you'll almost certainly need it for this job.