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Ok, a small update to my fix for the speed signal issue with converting to the to a digital signal...
The early cable drive speedo's pulse a ground for the Engine ECU and the P/S ECU. The cruise speed sensor does the same thing so there is no need to use a transistor as I said before. Why toyota added the sensor on cruise equiped cars is beyound me. It seems they only did it on Manual trans cars, but not on auto trans cars... Auto trans cars have the cruise speed signal tapped off the speedo head unit along with the other ECU's.... Basically the manual cars with cruise was a redundent adding of wiring and parts....
If you wanted to build a digital speedo using the cruise speed sensor for a manual car, you will need to build it in a way that is its looking for a ground pulse...
93 and later cars use a standard VSS and an electronic speedo. The VSS from these cars output a pulsed 12v signal. If you were to use a VSS, then you would need to use the NPN transistor as I mentioned above...
I built and tested the setup today and the only thing I have to add to what was mentions above is the need to add a 1k Ohm load resistor is needed inline one the base of the collector...
So to summerize the use of a 93 and up VSS (probably easier when doing a digital setup)
VSS signal to 1K ohm resistor to Base of transistor
ECU signal leads to Collector of transistor
Emmitter of transistor to ground
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