I'm getting annoyed with my light string, it turns on to a random effect out of 8 and all I want is an always on.

I managed to find this great website showcasing different controllers and how to bypass the logic to have the lights always on https://auschristmaslighting.com/wiki/Bypassing-Multi-Function-LED-Controllers

I have a very similar board to this one that I found on the website, it shows which solder pads to connect to make the lights always on without any effects.

enter image description hereenter image description here

Here is my controller

enter image description hereenter image description here

By the looks of it, the only difference is the 4 transistors(?) on the board from the website, whereas I have only 2. If the same logic applies, soldering the last 2 pins before they breakout into the separate leads will work? Maybe? I don't have enough experience in electronics to figure out which pads to connect together, maybe someone has an idea.

Thanks :)

  • 1
    \$\begingroup\$ What is the input and output of the controller? How many lights? \$\endgroup\$
    – JACK
    Commented Aug 14, 2019 at 15:07
  • \$\begingroup\$ @JACK I would guess ~50 lights. My board picture from left to right - left lead I would guess is ground to the lights, the next 2 are outputs to the lights from the transistors(?), final 2 are incoming live and ground 220V AC \$\endgroup\$
    – Matt
    Commented Aug 14, 2019 at 15:15
  • \$\begingroup\$ so that board has 220VAC as an input? I would have thought there would be a transformer somewhere reducing the voltage to say 12VAC. \$\endgroup\$
    – JACK
    Commented Aug 14, 2019 at 16:29
  • \$\begingroup\$ Does it have a a transformer from mains to LV AC - usually 12 or 24 VAC. 4 diode aare a rectifier bridge. You have cunningly hidden the connections to your leads in your otherwise extremely well done photos. Knowing 1. What the actual AC input voltage is 2. What connects where - will probably allow a good answer. \$\endgroup\$
    – Russell McMahon
    Commented Aug 14, 2019 at 17:05
  • \$\begingroup\$ Belay that. Photo etc not needed. See answer. \$\endgroup\$
    – Russell McMahon
    Commented Aug 14, 2019 at 17:15

1 Answer 1


This "should" work.
2 transistors are driven by control IC.
Connections as shown shorts transistors.

enter image description here

That's about as nice a set of photos as I've seen with a question.
A welcome change.
Sharp, well lit, shows area of concern. Leads were initially not 100% clear but once my brain engaged (5am - up to shake off a nightmare :-) ) it was clear enough.

Why is the left hand common lead +ve and not -ve?

And even rougher :-).
Here is why the lh trace is +ve.
On the copper side image all diodes "point right" - diode cathodes right.
So, if AC goes to an Anode the Cathode is DC positive.
If AC goes to a cathode the anode is DC negative.
In this case the 1st and 3rd diodes from the top have the AC input connected to their Cathodes (rh side/ bar end in copper view) So their Anodes are DC positive and are joined together and have a trace running to PCB bottom left - which is thus DC positive.

A multimeter set to volts will confirm this.

Presumably (he asked again) there is an AC transformer and AC mains is NOT connected directly to the PCB.

enter image description here

  • \$\begingroup\$ Thank you thank you thank you! I figured it was these leads, but I wasn't 100% sure. Finally don't have to roll the dice of the lights being just on 1/8th of the times I turn it on :)) Thank you! Edit: Oh and thank you for labeling the traces, I would've thought the left common was actually negative just by.. guestimating.. \$\endgroup\$
    – Matt
    Commented Aug 14, 2019 at 19:02
  • \$\begingroup\$ Wow.. Thank you for that explanation! It makes so much sense when explained like this, thank you! To confirm - 220V AC mains power is directly connected to the board, there is nothing inline between the plug and the board. i.imgur.com/wideunx.jpg \$\endgroup\$
    – Matt
    Commented Aug 15, 2019 at 12:12

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