The project started with an LED TV with presumably defective backlight strips. It’s time to find out:
Internally, the LED strips are connected in two different series loops, and markings on the TV PSU indicate that these loops shall be driven by 100V and 111V respectively.
I connected the test instrument to one loop, set the voltage adjuster to 0, selected mode: TV-TEST, and then gradually increased the output voltage.
At 80V, the LED loop start to conduct significant current, and the 20mA current limit kicks in. This makes me suspect that some of the LEDs in this loop are shorted, lowering the total voltage drop.
On the other LED loop, I could raise the voltage up to 120V, without any current draw. This is an indication of an open circuit somewhere in the loop.
I ordered new LED strips, and the TV was brought back to life 🙂
Other usages:
Retronics 
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