I've been thinking about modifying the odometer and trip in my dash for a while now, and I think I have a solution in hand that I'm not quite going to reveal yet, because I have a couple questions I need answered first.

Firstly, how does the car store the odometer information? Is it in the ECU or is it a chip on the dash cluster or what?

Secondly, how is that information transferred from storage to the actual odometer or trip? Is it mechanical or electrical?

The second question is more important than the first - honestly though I have no idea how the thing works, I just know it rolls over every mile I drive (or tenth of a mile) and looks dated, and I want it out of my dash. lol

Thanks in advance for any help.

They are both 100% mechanical. The ECU doesn't set the numbers or anything, otherwise it'd just be a digital display.

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As in there are tiny little gears spinning my trip over when I drive? We're sure it's not a mechanical display powered by voltage to drive an electric motor to spin the trip?

speed signal comes in to the speedo/odo and spins a motor which spins the odo

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Excellent. Would there be any way to split that signal into a seperate computer/chip which would then count up based on voltage input over time? It seems like I need to know how the speedometer reads speed, which IIRC is via voltage - higher voltage, the more the needle moves up, which is a signal sent from the transmission. Correct?

not quite. the signal from the transmission is more of a square wave which the frequency is relative to the speed.. look around and see if there are any gauge clusters that the odo/trip computer is in the cluster its self..

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7th gen cluster swap is out of my knowledge range.

I thought frequency was relative only to sound - you're telling me the transmission is sending an electronic square wave transmission through a wire to my dash?

basically. its using a magnet and reed switch to create a pule with varying freq to your speedo (square wave)

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That's nuts - and definitely shoots my idea for an LED counter conversion, I think.

7th Gen Clusters work the same way then and that's why they're readily swappable with a lot of work and re-pinning?

idk where you think i said gen 7 from lol. but yet im sure you can swap the electronics for the odo over from a gen 7. lots of time and guessing though.

toyota wouldnt change how the trann transmits the signal, they'd lose backward compatibility and have to update part numbers for something that has little to no selling advantage

thatd be cool to do. i want to go completely electronic, but im no car expert. i would like to have it where it'd be l ike 450 miles till e or something of that sort ya know

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It was a random question lol.

I wish I knew more about this sort of thing, I think a flush mount LED display would really help bring the dash up to date.