I think your meter is fine.

Regards, Dana.

 

I think your meter is fine.

Regards, Dana.

i think its fine now. but before it wasnt but thank you guys for help

 

my meter does the same thing again. but now hwn i touch negative lead its shows normal voltage and when i touch positive lead its show about 17 volt instead of 5,20 volt. and when not touching its shows 7,5 ors so volts instead of 5,20 volt :/ what is going onnn

 

Don't think so.
Say you connect the meter to a battery then press the relative button. I would expect the meter to show zero. Then connect a load to the battery and as the battery voltage falls the meter would indicate a negative voltage being the amount the voltage is now less than the original measurement. So the meter indicates the voltage relative to the reading when the button was pressed.

Neat, I never used that function. Just tried it out and it works exactly as you described. Shows the amount of V that changes from when you set it. Lower or higher.

 

Also remember that voltage drop thru a diode only happens when there is current through it. And, less current will give a bit less voltage drop, more current will give a slightly higher voltage drop.
You cannot measure voltage drops across a diode out of circuit unless you pass current through it (as in Diode test mode on most multimeters)