....because it was of wrong size.

Hi all.

I have a '91 Firebird with L03. Yesterday I started replacing some blown bulbs here and there, including the module where you adjust a/c, heater etc. While I had the panel open I saw that my cd has a dimmer option and started looking for a place where to connect the cd's dimmer wire.

While measuring the sockets where those bulbs go I accidentally short cut the socket and since I apparently had a 20A fuse instead of the 5A that's supposed to be, something else melted.

Having debugged for a while the problem seemed to be a melted wire between the instrument panel illumination dimmer slide and the fuse box so I replaced the wire. However the problem wasn't quite this simple to solve: now the dimmer slide heats heavily and even smokes ( ) and the adjustment is nowhere close to linear.

Now the wires that come to the i/p dimmer are not what my Haynes / Chillton manuals show, they say that a green wire comes to the i/p dimmer but not in '91 fb. In my case the wire that has regulating voltage is black with red stripe and it goes somewhere inside the instrument panel but ends up green in the fuse box. The wiring is original, no mods there (nor anywhere else).

Does anyone happen to have a more detailed diagram of the dimmer and it's wiring than this: https://www.thirdgen.org/schematics/...ghtSwitch1.jpg ? It seems that I can't just disable the old wires and install a new one from the dimmer straight to the fuse box.

Oh and thanks all, I've been browsing your site for a couple of years already but now it was finally time to register and send in my first post!

 

Yep, this transistor was blown and it's completely missing from all the manuals (haynes, chilton) that I've seen.

It's an npn transistor that has base +12V (brown), collector input (black w/ red stripe) coming from the slider switch and emitter (dk. green) sending out the regulated voltage. Enjoy.

http://liberte.fun.sonerazed.net/mis...transistor.jpg
http://www.komppi.com/fbodystuff/misc/saadin/

 

That seems to be a common trend given that they really only cover one year and trim level in exact detail. If you poke around, I'm sure that you will find lots of "hanynes didn't show _____".

While they are a great resource, they are not the be all and end all.

 

That transistor that you are referring to is the remote dimmer module. You will also find that there are a lot of things that are not covered or not covered very well in the haynes and chilton manuals.

 

Transistors regulate current .

 

Forgot to mention that the transistor is some Motorola made but GM labeled so there's no way of knowing what the original transistor is.

The one that I used to replace the original is 2N3055 in T0-2 cover. It should be a rather common transistor.

 

No they don't. Not without help from other parts anyway. Like saying a block makes power.

1986902-2 This IS a Motorola part number. If you are have problems crossing it try an older cross reference. ECG and SK should both have a cross for the part number. I know that's the right format for a Motorola part number anyway.
It just doesn't look like a re-stamp part.

 

A "normal" transistor does not regulate voltage, thats what a JFET does. Obviously a transistor doesn't just regulate current, that's not even close to what I was saying.

 

Looks like it to me.
A transistor (Bipolar, FET, MosFET, JFET, UJT) can't regulate nothing, current or voltage unless it's in a regulator circuit(you would use a Bipolar here). How is an output transistor in a amp regulating any thing?

 

Well the definition or regulate is: " To adjust to a particular specification or requirement:", so transistors amplify current in a power amp (they aren't amplifying voltage).

P.S. "can't regulate nothing" is a double negative...

 

If the load stays the same (4ohm), voltage must go up if current is going to go up. See some constant current sources and how they work. To maintain a constant current they vary the voltage. E=IR If R stays the same E must go up in proportion to the increase of I. Say you give a (in this example car) amp 1Vp-p on the input, I hope you see more then 1Vp-p on the output. This is voltage gain (now you have more then you did) or amplification. Current amps will amplify current, power amplifiers amplify both voltage and current. You will often see output voltage from a car amp at MORE then 50-60Vp-p, from a 1-8Vp-p signal input. All this with 12Vdc input power supply, but man can they pull some current.

I am thankful for the grammar help (btw that was in part to lighten things up, unfortunately inflection don't work to good over da net ), but this was a technical thread. If we are going to have a reasonable discussion I think the best course would be to focus on the topic at hand. I didn't think this would be a big discussion, just thought your original post was a considerable over simplification at best.