Tek DPO3054 stuck in endless video test loop

[pets57]

Hi all,

My Tek DPO3054 is stuck in a continuous, unstoppable video test mode. It cycles full-screen splash colours every 15s or so then briefly returns to the post boot 'power-up self test passed' screen with push menu off, etc. Nothing seems to stop it!

This occurred after running an SPC which passed fine. However, after that I noticed the Error Log screen contained a whole bunch of low-level 'Manufacture Test' options one of which was 'Run RTC OK'. Inadvertently I pressed this and now it continually cycles this damn video test loop!! 

Nothing stops it - cycling power, re-installing firmware, etc.

Help and thanks in advance!!

Pete

STOP PRESS - Ive sorted this - solution below.

The firmware version v2.14 for the DPO3054 contains a 'manufacture test mode, accessed by pressing the 3rd then 4th side buttons when in the Error Log screen. This is useful when debugging an SPC fail (i.e. confirming that a recal will fix). However, when in this mode there are some buggy tests (or tests that should not be used without further system knowledge) as described in my original post above. This is not available in later firmware versions. Btw, I was first put onto this v2.14 feature by Tek support when trying to debug an SPC fail as it has a menu option for showing more error detail and erasing the error log.

When stuck in this endless unstoppable video test loop there is a 2-3s gap every 15s or so when the normal scope screen and user controls are active. Patiently navigate to the Utility/Self Test/Self Test screen and select Abort Self Test - you will see this weird behaviour is actually a  stuck in video test mode. Aborting this self test fixes the problem.
Lesson learned - 'don't mess with low level diagnostic test modes without detailed knowledge'!

Pete