Thread: LED Dash lights
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Old 08-16-2020, 02:38 PM
Grand73Am Grand73Am is offline
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Quote:
Originally Posted by 76TA462 View Post
Looking at the back of a spare tach and speedo cluster I have, I pulled one of the twist in housings that hold the 194 bulb. I can't see any way of determining polarity. If I put it in wrong is the only outcome that it doesn't work. Looking at a general blog (no idea what car type) there was a comment that I could burn out all other lights on the same circuit if I put in the LED with wrong polarity. I am looking at the Sylvania bulb but it has polarity. They aren't cheap but going through some reviews of LEDs a common theme is that the better ones are more dependable, last longer, etc. Thanks again.
There isn't any way to determine the polarity when installing the bulb. It's trial and error. If it doesn't work, it's in the wrong way, so you pull the bulb back out, turn it around and plug it back in and it should work. It doesn't hurt anything to put it in the wrong way. It just doesn't light up. I used some Sylvania LEDriving LED's that were polarity sensitive a few years ago when I did mine. So, it took a couple times re-installing a few of the bulbs to get them turned the right way so they would light up. After that, no problem. If I were doing it now, I would buy LED bulbs that are NOT polarity sensitive to avoid having to go through that again.

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