Getting different voltage when using blink (is this bleeding ?)

So, after while of using it, my arduino started behaveing wierd. The integrated LED burned out for unknown reason and I atteched another external (whithout a resistor) to pin 13. It was working quite well, the light came out normal and solid, but after while the LED started blinkig like a strobe, as if I had put a delay under 200ms . The problem is that I havent. It blinks interupted for the amount of time I have put in and then stops. I have checked the pin with a voltmeter and there seems to be something strange. I get 0V and 4,5V for 2-3 times and after that I get some other different voltages. For example 0V, than 1,2V, than 4,5V, than again 0V, than this time 2,3V, and after that 4,5V. And this happens till it reaches the maximum of 4,5V and starts all over again.

Is this normal ? Am I getting this wierd blinking, because of the LED, or have I burned my arduino ? Do you get the same results when you attach a voltmeter to your arduino, while using the Blink example?

The Arduino board might be broken.
Did you use a resistor and a led ? You should not connect only the led to an output pin.

However, the onboard led burning out is very weird. When you bought an official Arduino board, you might try to return it.

Or did you have a loose wire with 12V hanging around the Arduino ?
How do you power the Arduino board ? Using the usb bus is safe.
Disconnect everything from the pins and measure the the 5V pin and the 3.3V pin, are they okay ?

The actual voltage that you measure has little meaning. A low voltage can be a broken board, or a pulsed output, or a shortcut on the board or trouble with the power supply.

Sounds like a bad solder connection on the Atmega-chip.

Some of the clone boards is very bad soldered. You get what you pay for!

// Per.

Yes, clones have bad quality, but for the price it is normal. I have found that thing that I have wrote in my first post doesn`t bother me at all. It still works good enough and I can manage to do things with it, so it is not even a problem.