UPDATE: Please HELP! Both of the turn signal light fuses blow
 

I tried to add some rear lights to my 2003 H2 by splicing into the trailer hitch harness.
I was very careful to splice into the correct wires.
When I used my turn signals left and right, I heard the flasher relay clicking very fast then thetwo 10 Amp turn signal fuses (one for left and one for right) inside the side panel blew!
I immediatly disconectedmysplice connections, restored everything as from the factory and installed two new fuses, tried the turn signal lights and the fuses blew again!
I replaced the flasher relay ($65) and installed two new fuses again and tried the turn signal lights and the fuses still blow!
SOMEBODY PLEASE HELP!


After extensive troubleshooting, I figured it out.
Some electrical circuits on an H2 such as the turn signal circuit and the marker lights circuit have there own return circuit grounding path.
Chassis ground is NOT part of the turn signal and the marker light return grounding circuit.
By adding some external lights by splicing into these circuits and grounding through the chassis caused the turn signal fuses to blow.
So extreme care must be taken when adding lights and what circuit you splice into.
Thank you all for all your advice.
Safari Hummer H2