No tengo señal en mi iPhone. Cambio el chip a otro iPhone y si tengo señal

Were you able to try a reset of your iPhone, to see if that helped the phone get a signal?

Troubleshooting the issue may also involve returning to an authorized sales/service

provider to have the unit checked over and tested, in case some defects may exist.

http://www.apple.com/support/iphone/

For service support check the Locator page

and use your nearest city to see who's there.

http://www.apple.com/support/iphone/contact/

Although you've tested the chip from your iPhone in another, and it seems to work,

there may be some other problem in your iPhone; if a reset or other action may help.

To see some helpful articles about setup and use:

http://www.apple.com/support/iphone/using/

Sorry that I haven't a specific course of action to resolve the issue.

Good luck in any event! 😐