I was replacing some lights in my car's HVAC control box, and I used 12v 60ma bulbs (link), and after reinstalling it in the car (bulbs are working), I was doing some Googling and noticed that some people are using 14v 95ma bulbs. Lets say that a voltage or current spike occurred and pushed 14v ~95ma, am I in danger of damaging the electronics/PCB, other than blowing the bulbs?

  • \$\begingroup\$ These are not LEDs... \$\endgroup\$ – Eugene Sh. Feb 11 '15 at 21:15
  • \$\begingroup\$ My bad. They're incandescent. I'll update the question accordingly. Question still stands. \$\endgroup\$ – IAmTheSquidward Feb 11 '15 at 21:21
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    \$\begingroup\$ There is a high probability that it will work, but the intensity will be brighter than supposed, and the lifetime will be shortened. The current rating is not a problem here, the voltage is. \$\endgroup\$ – Eugene Sh. Feb 11 '15 at 21:25
  • \$\begingroup\$ I figured the voltage is the problem. Is there a probability of damage to electronics other than the bulb just dying? \$\endgroup\$ – IAmTheSquidward Feb 11 '15 at 21:27
  • \$\begingroup\$ Unlikely (I can't think of such a scenario) \$\endgroup\$ – Eugene Sh. Feb 11 '15 at 21:29

It is unlikely that you will damage the electronic module because your bulbs draw less current than the proper bulbs. However, they will not last as long as bulbs of the proper voltage rating.

The problem is that the DC voltage in a 12V automobile sits right around 13.8 Vdc when the engine is running. Bulb lifetime varies by about the 12th power of the change - that means that a small change in voltage makes a huge difference in bulb life.

  • \$\begingroup\$ "Bulb lifetime varies by about the 12th power of the change" - Very interesting, what's your source? \$\endgroup\$ – Mister Mystère Apr 13 '15 at 14:47

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