LEDlights/bulbs ????
Post Fiend
Joined: Oct 2007
Posts: 10,501
Likes: 5
From: Faibanks Ak.
That would be right because when leds first came out for semis one thing that was pointed out was when the voltage dropped to I think it was 9 volts they were just off they didn't keep dimming until the battery was dead.
Cargo Master
Joined: Feb 2008
Posts: 3,409
Likes: 1
From: back in SE Iowa
i hooked 2 up to 2 AA batteries which is 3 volts and then hooked them up to a 9v with a resistor and the 9 v was way brighter
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Lead Driver
Joined: Dec 2006
Posts: 6,496
Likes: 94
From: So. Jersey
What I'm saying is if you have 4 LED's in series that require 3.2 volts each, that is a combine required voltage of 12.8 volts or battery voltage.
Now run them through the rheostat (headlight switch dashlight adjustment) and you will lose that infinite adjustment. They may get a little less bright, but you won't be able to set them real low like an incandescent bulb. Much like a florescent bulb.
Cargo Master
Joined: Feb 2008
Posts: 3,409
Likes: 1
From: back in SE Iowa
i see what your saying.i was using 3v resistors so no more than 3v went to each led.i cant recall the numbers for the resistors though.im still really a noob when it comes to the electronics thing when it comes to resistor ,capacitors ,and diodes and such
Lead Driver
Joined: Dec 2006
Posts: 6,496
Likes: 94
From: So. Jersey
Alright cool, atleast I was able to explain myself so you knew what the heck I was trying to say. When I get back from a trip I'm going on I have a H/L switch to try this on with some colored LED's. I'll let you know or if you have a rheostat you can try and post it up.
Posting Guru
Joined: Dec 2005
Posts: 1,528
Likes: 0
From: Peterborough, Ontario
I forget which truck, may have been my F150, but one of them the wire wound resistor burned out and was causing me grief. Took a while to find it, but once I figured out the problem, a few seconds with wire cutters and the resistor was gone. The dashlights would only work with them turned to the brightest setting, but, that's where I usually have them anyway.
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