Q: No start and no crank. I hear a noise from one of the relays - 2006 Chrysler PT Cruiser

Depending on the type of noise you hear, this may be related to the starter relay or starter solenoid. The starter solenoid is a small unit on the starter that has internal electrical contacts that transmit electricity to the starter. When this is faulty, this will produce a clicking kind of sound when you turn the key. This is usually the pinion gear moving forward inside the starter and rotating when it should not.

I would suggest having a professional, such as one from YourMechanic, come to your home to diagnose why your car is not starting and determine the source of the noise.