How To: T50 Electronic Speed Sensor

[TERRA Operative]

For those looking for one of these things, you'll find them on the following cars.

Japan:
Corolla AE100/EE100 3FC 1991 ->
Sprinter AE100/EE100 3FC 1991 ->
Carina ED ST200-ST203 Auto 1993 ->
Celica ST202 Auto 1993 ->
Celica ST203 Auto 1993 - 1997
Corona EXIV ST200-ST203 Auto 1993 ->
Caldina ET196 3FC 1993 ->
Camry/Vista CV40, SV40-42 Auto 1994 - 1996
Camry/Vista SV42 1996 - 1998
Camry Gracia MCV21, SXV20 Sedan 1997 - 1998
Avalon MCX10 1995 ->


Australia:
Yaris/Echo NCP12 Auto 2000 - 2005
Yaris NCP93 Auto 2008 ->
Corolla Sedan/Coupe/Wagon AE100,101, EE100,101 3FC 1992 - 1999
Corolla Sed/Wg ZZE122 Auto U341E trans 2001 - 2007
Corolla Sed/Wg ZZE122 Auto 2005/10 - 2007/08 (any in Aust)
Camry ACV36, MCV36 Auto 2002/08 - 2006/06 (any in Aust)
Avalon MCX10 1995/08 - 2005/06
Previa/Tarago ACR30 Auto 2000 - 2005

[styler]

good find

[thanhngo]

Excellent work, would anyone know how many pulses/rev these units output?

[greenmac80]

+ 1 for the above question except to calibrate speedo's you need pulses per kilometer.

although i imagine this is dependant on wheel size etc. also diff ratio.
so anyone one on here that has done this can you please provide specs of your car and your findings?

[thanhngo]

I think those are 4 pulses per rev (common across some toyotas).

I ended up using one from a 90's model pulsar which is 7 pulses (screw onto the T50 using an adapter) for my non-factory speedo. You can also use speedo adjusters to multiple/divide to get the right frequency for your tacho (as long as theres sufficient scale) so it can adapt to different wheel size/diff ratios etc.

[greenmac80]

ok so using that how can you calulate how many revs per km? any ideas?
i am a bit dumb when it comes to this stuff.

[takai]

Yeah, these newer ones are 4/rev. Working out pulses per km is just a matter of going through all the ratios down the drivetrain until you get to the wheels.

[greenmac80]

hmm yes and how do you do that?
so if the diff is 4.11 does that mean the tailshaft turns 4.11 times per 1 revolution of the wheel?

[TERRA Operative]

You can get a converter kit from Jaycar that will allow you to calibrate the signal.
Hit the freeway at 100km/h with a GPS to work out your speed correction in % and dial it in for a correct reading, easy as.
We used one on my brothers old EF Falcon when we put a lower ratio LSD in, worked a treat.

http://www.jaycar.com.au/productView.asp?ID=KC5435

[greenmac80]

cheers for that!! well i have a good starting point.
per km my wheel spins 551 times this is based on rim size and tyre size
my diff ratio is 4.11 and the sensor pulses 4:1

so using my trusty calulator i get. 9058.44 pulses per km. so i'll set the speedo at 9058 and then get the gps out and see where i'm at!

[takai]

Remember that you have the ratio of the sender in there too. The end of the gear should have something printed on it, like 33:9 or similar.

Oh as well lots of the older Toyota speedos are 637revs/km

[greenmac80]

ahk shit i didn't know about the gear having a ratio... hmm.
i'll have to check it... good info about the speedo but my speedo is a speco one so the revs/km isn't usefull to me.

[takai]

Yeah, but it gives you a ball park figure to work with for approximately what your answer should come out like.

[greenmac80]

ahk i thought the answers would be totally different due to the new sender being electronic.
whereas the number you've given me is cable driven? revs vs pulses?

[takai]

Yeah, but the number of revolutions is the same up to the sender. The cable just translates the motion to another location. So if the dash is expecting 637revs/km then as it comes out of the gearbox (so long as your speedo gear drive matches your diff ratio) will be 637revs/km. You can translate that into pulses/km by simply figuring out what model sender you have and then applying the right number of pulses/rev.