No display but tracks

hi . Installed headset the other night all ok for display.
Turn on today no display. pi play detects unit ,and so does steam. but nothing on screen . green light on top is working.but nothing else happens. when i initially got it working the screen was on all the time .and i thought the sensor should be turnig it off .but i was just glad it was working.
.Iinnitialy the first time on was just about 20 minutes cause it was getting late. My system comprises of Win7 64bit running a gtx1070 with an i7cpu.
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I assume you’re using the latest firmware and Piplay?
FW 1.0.0.248. Piplay 1.2.53.

In Pimax mide, going by my unit, the led on top of the HMD should be blue.
If you look at the HMD screen, do you see a Pimax logo.

If in Video mode, led is still blue but the HMD screen displays a desktop pic as on your pc monitor?

If not like that, try uninstalling and reinstalling Piplay again.

Make sure you install as Administrator.

Hope this helps.

I have similar issue.

My Pimax start I can see logo. then I start steam, 10 seconds and led goes right, display goes off.

Do you mean it stops working after 10 seconds?
What colour is the LED?
Do you mean SteamVR?
Do you see the SteamVR background in the HMD?
If you are not wearing the HMD the display will go off.