On 14/04/2021 04:43, micky wrote:
>
> What are the devices in these two parts of a schematic
>
>
https://imgur.com/a/mnnzq3O
>
> On the left is probably the lighting for the 2005 Solara trip computer.
> The schematic calls it the Upper Console Panel Sub-Assembly which I
> think is the part above the radio (but the schematic lists the clock
It's not a electronics schematic, it's a electrical wiring diagram for
auto mechanics. There is a lot that Toyota have chosen not to display,
lest you not buy their spare parts as complete modules. But they have
given you a general sense of what they do.
> I understand the LEDs but why zener diodes, and another diode (since
> there is 12V DC at the top and ground at the bottom)?
Zener diodes to avoid spikes killing the LED, reversed biased they will
clamp the voltage to a maximum.
The other diode is reverse polarity protection, as generated by spikes,
faults or mildly idiotic users.
> On the right is almost all of what the Toyota wiring manual calls the
> combination meter, meaning the speedometer and other meters in the
> instrument cluster. I aassume the "rheostat" is the thing it has to
> adjust the brightnees, that the LED (or more than one) provides the
> light, but what are the strange things at the bottom and to the right.
>
N-Channel Mosfets.
https://en.wikipedia.org/wiki/MOSFET
> They look like they are connected to transisors, but they have the 3
vertical lines, one of which in each set has a left-point arrow.
Try a post to sci.electronics.basics
>
> The manual has a list of symbols and it has LED, photodiode and zener
> diode, but not the strange things in that picture.
>
The actual reality, choice of parts etc... is up to Toyota.
>
> BTW, was this an appropriate post for Imgur? Most of their posts sseem
> to be more entertaining.
For displaying pictures for us, certainly. Preferable to the other two.
>
> I though I had flickr and instagram but I can't find the login info. I
> don't understand all this computer stuff.
If you don't understand "two factor authentication / two step
verification", I'd step very carefully on the internet, and close down
what you don't use.
As far as I'm concerned, Instagram is for kids.
--
Adrian C