QuestionIve had my car stereo for years but suddenly the display says " protect" and my stereo wont work - I tried reading up on it - but all i could get was some info about a 4 digit security code which i never set up - b/c i never got the remote with the stereo - can you help?
AnswerHi Katherine,
Sorry about the long delay in answering this question.
When a Kenwood head unit displays a "protect" message, it's not related to the anti-theft code. It's telling you that the unit's internal amplifier has been shut down for protection. This usually happens because of a short circuit affecting the speaker outputs. It can be caused by a defective speaker, a pinched or shorted speaker wire, or an internal defect in the head unit.
Your deck should have a "reset" button built into it; either on the front faceplate, or on the front of the chassis when the detachable face is removed. It's a very small, recessed button, designed to be pressed with a pen tip or the end of a paper clip. Pressing this button might clear the "protect" condition and get the unit working again, but if it was caused by a short circuit somewhere, then it's only a temporary fix.
If I was troubleshooting the cause of this problem, I'd start by removing the head unit and testing the speaker wires for short circuits. This is done with a multimeter set for "continuity". I'd test to see if any wire was in contact with the vehicle's chassis metal, and I'd also test the DC resistance through each pair of speaker wires. If a problem is found with one speaker, it can be disconnected, allowing the head unit to work normally with the other three.
If no problem is found with the speaker outputs, then I'd suspect an internal short circuit in the head unit. In this case, your best option would be replacement.
Hope this helps!
Brian
