How to Block HDMI-CEC

by Rian

This week is a home theater special. If you have just upgraded your home theater during Black Friday, chances are you are probably facing the same problem as I do. The infamous HDMI-CEC; it doesn’t work. The last time I had the pleasure of working with HDMI-CEC, which happens to be today, it was waking each other up endlessly like network live-lock.

Before I get into details, the ultimate “fix” to the problem, aside from radical redesign of HDMI-CEC, is to set each devices to ignore HDMI-CEC. CEC technically works when there are only two devices in the loop —a TV, and perhaps a receiver. But even in my own setup, that is not an option; both LG TV and Bose Soundbar require HDMI-CEC to work via ARC, and some devices still ‘listen’ to HDMI-CEC even though it’s disabled to control via CEC.

Instructions

I’ve tried three different tapes for this endeavor, and you do NEED an electric tape. It’s the only kind that can hold itself on the connector, and it’s the only kind that can actually block out the signal from the HDMI port.

1. On either side of the male HDMI connectors, we want to block pin 13. To locate pin 13, hold the connector with the narrower side facing bottom. It’s the 4th pin in the top row (wider side) from right.
2. We also need very slim strip (few millimeters at most) of tape to cover the pin. It only needs to block the hole, so don’t worry about covering the inside. What you do need to consider is NOT blocking the other pins.
3. Once done, gently insert the HDMI connectors back into the port. Test if HDMI-CEC is properly blocked.
   

At first, I wanted to use my go-to black paper tape as it is easier to remove and less likely to damage the port or the connector. Paper tapes or cellophane tapes can’t block the signals without getting it too thick. My dexterity issues weren’t helping at all. Using a tweezer and a spudger from a toolkit helped.

I got the inspiration to look for tape-based solution when I found a Korean blog post mentioning I could stick a needle into the pin 13 to destroy (i.e. dislodge) it. I suppose it would be easier to mangle a cable. If you have HDMI cables lying around and don’t want to mess about with electric tapes, it is certainly a possibility. Also, —I will probably write a separate op-ed for this— there are HDMI-CEC blocker adapter on Amazon; it would be the safest solution out there, albeit it might be HDMI compatibility nightmare of its own in the future.