Instrument Cluster Bulbs

[bigbengalbubba]

I have a 2003 1500hd. I recently replaced the stepper motor for the speedometer which was no big deal. Now one of the bulbs is not working. I know they are soldered in and I have worked in electronics for many years so soldering is not a problem. I am just wondering if anyone knows if I can get the bulbs at a local parts store and what type they are?

Thanks.

[Draenor]

I would doubt that the parts store would carry these. A place such as Radio Shak would...if thats what you meant by parts store. I tried searching, but cannot locate a bulb ID.

[bill190]

How about an LED and a resistor in series on one lead?

 

I would try a 1K resistor to start with. See if that is the same brightness as the other bulbs. Then go down to about 750 ohms for more brightness or up to 1.5K or 2k ohms for less brightness.

 

Also the LED's they sell these days have different brightness levels as well as colors. Then they go and use different units of measurement of the light output, so hard to tell which are brighter/less bright when going "LED shopping"!

 

So might want to get a couple of different LEDs and try them out.

 

I got fed up with a dome light constantly burning out in my car, so I replaced it with a super bright LED replacement. Problem solved!

[peteking]

Hmmm...Which forum member switched out all of his bulbs with LED's? I forget who it was, but I think he drives a black GMT400. A while back he posted some detailed proceedures. A quick search will probably find them, as they contain lots of helpful info.

[peteking]

Ah-HA! Kyle did it....that's right.

 

http://www.gm-trucks.com/forums/index.php?...l=gauge+cluster

 

Sure it is specified for GMT400 trucks only, but some of the proceedures should be similar/identical.

[bill190]

That might be quite helpful as to the specification of LED and resistor(s) used. It used to be you could tell the brightness of a bulb by the "lumens", but with LED's, they have all sorts of units of measure. Here are my notes on the different light output units (quite confusing!)...

 

LED/Lumens...

 

lm is total luminous flux flowing from the LED in lumens

 

(mlm=millilumens)

 

cd is the luminous intensity in candelas of the light

 

(mcd=millicandela)

 

mlm, a unit for luminous flux, corresponding to 1/1000 lumen

 

4700 MLM = around 7000 MCD

 

1000 millicandelas @ 30 degrees beam pattern = 0.214 lumens