Help Headset mode stays on , when they are not connected

[Andrea Silva]

I'm studying electrical engineering, today I was doing a circuit project and I connected my cellphone to a jack and the jack to a circuit. Aparently voltage enter by the jack and now my cellphone is stuck in headset mode. I tried taking out the battery, slowly connecting and taking out the jack, blowing it with a hair dryer in cold for 30 seconds, I cleaned it with a Q-tip and nothing worked. Someone nows what can I do ?

 

[lunatic59]

If you applied voltage to the headphone jack, you most likely burnt out a circuit, or fused one closed. I don't think there's much you can do other than replace it. What kind of phone is it?

 

[mikedt]

Sounds very much like something, probably a chip got fried when you applied voltage to the headset jack connections. Which very probably means a replacement logic board or module will be required. Could try a warranty claim, and just say it went like that. There's no obvious splat marks visible is there?

Something I learned with electronics years ago, is that a semiconductor(usually an expensive or irreplaceable one) will blow much faster than any traditional fuse can.