Well I connected it up with extension and power via USB.
It blinks white at the back but no picture on the screen?????
I took the USB out and back in.
The light went white on, then red, then began blinking white again????
No picture on screen?
Do I need external power?
What do I need to try?
Do you press the button on the Chromecast?
Edit: Well I see for 2 secs Chromecast starting then black screen with USB power.
I can use my smartphone to connect to the wifi signal it beams out but I just have a black screen?
I connected to a PS3 usb for power and same result.
Rebooted\factory reset
Did that…went 30 secs….nothing then it went red, white and began blinking white again…no picture at all?
Googled:
1. Going to to try another USB cable
2. Pulled on it to see if a connection inside casing.
Should I put it in a monitor or another TV to test?
Seem to be able to click the button on side without issue.
Finding that disconnecting power via USB is not getting the Flash "Chromecast starting" on screen anymore?
Is there any HDMI settings on TV that you do?
Does it matter if 3 HDMI items are connected at once?
Make sure that:
Your TV is tuned to the same numbered HDMI input to which you connected your Chromecast. On most remotes, this can be done with an Input, Source or Menu button. You may have to cycle through a few inputs before finding the correct one (e.g. PC, Video, VCA, HDMI1, HDMI2, etc.).
You have plugged the Mini-USB end of the included USB cable into your Chromecast.
The other end of the USB cable is firmly attached to a powered USB port on your television or into the power adapter included in your box.
The light on your Chromecast is illuminated or blinking, indicating power.
If you still do not see the Chromecast home screen on your TV, try your TV's other HDMI ports.
If you saw your Chromecast's loading screen ("Chromecast" with a spinning Chrome logo) but the home screen is black, you could be experiencing an HDCP (High-bandwidth Digital Content Protection) with your TV. This issue is easily fixed by rebooting your TV. Turn your TV off, unplug it, turn everything back on and try again.
If you see a black screen or just a few colored dots when you power on the Chromecast, the reset button may be stuck. The reset button is the only button on the Chromecast itself. In this case, try unplugging power from the Chromecast and pressing the reset button a few times to unstick it. Once the reset button is working, you should feel it click in when you press it and bounce back when you release it. Once the reset button is loose, set up the Chromecast as normal: plug it into the TV's HDMI port and connect the power cable.
Your issue sounds like the HDCP one (point six).
Source: Chromecast help