# Tiny bulbs in rear window defroster switch



## wavepacket (Jul 10, 2007)

I want to replace the tiny light bulbs in the rear window defroster switch. I was able to take out the switch (from the rear!) and disassemble it with a small precision screwdriver. I see two very small bulbs inside that are much smaller than the T5 and T10 bulbs that are used on the instrument cluster. What is the name of these bulbs so that I can find if anyone sells them online?

I already called the Nissan dealer and local auto parts stores, and they did not have the bulbs. The dealer did have the entire switch for around $70, but I just need the small bulbs, preferably LED equivalents that will last longer.

In general, where is a good place to buy Nissan replacement bulbs? For instance, I bought a nice set of T10 and T5 LED bulbs for a very low price off of ebay from China, and the worked fine and brightened up my instrument cluster. The only gotchaya is that you have to be aware of polarity when installing LED bulbs. I would buy again off of ebay, but I don't know how to refer to these bulbs to find them on ebay!


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## wavepacket (Jul 10, 2007)

I got out a magnifier and read the small print on the bottom of the bulb housing. It says TSD 077. Typing that into a search engine brings me to other forums. Ebay comes back with nothing. 

Still wondering where to buy this replacement bulb (LED preferred).


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## wavepacket (Jul 10, 2007)

Reading Having a tough time tracking down an interior bulb., a guy soldered in a 3mm LED since he couldn't find a replacement bulb


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## wavepacket (Jul 10, 2007)

Reading https://forum.planetisuzoo.com/viewtopic.php?t=58451, it looks like the bulbs are 7219 T-1. I'll have to thread the leads through the TSD 077 casing. 

12 voltage rating, 0.06 amps
Wire leads (wl) base, t-1 bulb
C-2f filament
0.25/6.4 mm mol, 0.13/3.2 mm mod
1.89 lumens, 10000 rated life

Any of you know of a brighter LED equivalent?


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## wavepacket (Jul 10, 2007)

I might be able to take a T5 LED bulb that I have and thread its leads through the TSD 077 casing. Requires to work through a magnifying glass since it's all very tiny. That will be brighter, which is what I want on this indicator. If not, I'll buy the T-1 from amazon, 10 for $7.27


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## wavepacket (Jul 10, 2007)

The only LED equivalent (WT121, WT122, and WT124) for a T-1 incandescent I've found so far is from an avionics place, and they only sell in bulk. Have not found an LED replacement on ebay, amazon, or aliexpress.

Avionics Applications Based LEDs Bulbs Chart, LEDtronics


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## wavepacket (Jul 10, 2007)

If you type '3mm led' into amazon, you'll find LED equivalents that you can use. Not sure if the wire leads are as bendy as with the T-1 incandescents. We'll see, since I'm ordering them now.


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## wavepacket (Jul 10, 2007)

If you replace with your typical 3mm LED from Amazon, you need to include a resistor in series to limit the current to 20mA. R = (12V - 3.2V)/0.02A = 400 ohms, where 3.2V is the forward voltage drop across the LED at 20mA. Make sure the resistor has a high enough power rating. In this case, P = (12V - 3.2V) * 0.02A = 0.176 Watts. Since this is a tight space inside the switch, I probably will use a surface mount resistor.


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## wavepacket (Jul 10, 2007)

Reading some of the reviews on the LEDs on Amazon, some of them are super bright. One guy recommends to reduce the current to 1 mA for the brights ones. This would make the resistor = 8800 ohms and the power dissipated by the resistor reduced to 8.8mW. Power consumed would be reduced by a factor of 20. At 1 mA, it would be 6 times more efficient than the incandescent bulb (and probably brighter, we'll see). I'll probably chose 6 mA current draw, implying R = 1467 ohm. This would make the window defroster indicator super bright, which is what I want.


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