Hi,
Have you tried using the Arduino on its own and see if the fault reoccurs?
Use serial monitor to display the readings.
A schematic of your complete project would help.
PLEASE do not use a Fritzy image.
Tom.. 
Hi,
Have you tried using the Arduino on its own and see if the fault reoccurs?
Use serial monitor to display the readings.
A schematic of your complete project would help.
PLEASE do not use a Fritzy image.
Tom..