My 2003 trailblazer has no power and keeps blowing fuses. why

Hello Kimberly Collett,

My guess is there are a couple of things going on...

You have enough years on the vehicle where you can worry about everything your heart desires... except the things you have recently serviced yourself.

OBD II or OBD2 (on board diagnostic) systems were pretty well standardized by the time your vehicle was manufactured... and are pretty cool at letting you know what the car/truck thinks is
OUT-OF-LIMITS... (typically plugs in under the dash-board).

My car started whimpering about oxygen sensors... took me a while but I finally figured out it was a collapsed catalytic converter.

There is a significant list of items which will put your vehicle in "LIMP" mode... (restricted engine use intended to get you to the DEALERS CASH REGISTER... or safely home).

Without an OBD READER you don't stand a chance.

As to fuses... If you let us know... fuse number, activity during failure... engine size, accessories & what fails... I would be willing to tell you something better than the capacity of your LOAD has exceeded DESIGN parameters your fuse is designed to protect (from fire, damage, destruction & possible injury).

Good luck...