MY KENWOOD CAR CD PLAYER IS SAYING PROTECT??
Kenwood head units show "protect" when there's a problem with the speaker outputs. This might mean a shorted speaker wire, a blown speaker, or an internal defect in the head unit. Once the condition that's causing the "protect" mode is fixed, the CD player should be back in normal mode the next time you turn it on.
If it's staying in "protect", then you'll definitely have to remove the stereo and do some troubleshooting to fix it. Many car audio stores will do system troubleshooting, for a fee. If you want to do it yourself, here's what you need to do:
Pull the Kenwood unit from the dash and disconnect all the speaker wires. Turn it on and see if the "protect" message displays. If it does, the stereo has an internal defect and will need to be serviced. If it doesn't, then turn it off, and re-connect one speaker. Turn it on again and see if it displays "protect".
If it works with a single speaker connected, keep re-connecting the others until you identify the speaker that's causing the problem. There may be a wiring problem or defective speaker in that location.
If it displays "protect" with a single speaker connected, then disconnect that one and try a different one. If all the speakers cause a "protect" mode, then you're probably back to a defective head unit, unless your friend managed to blow all your speakers at once.