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Digital speed inputs


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Hey guys.

Ive played with the thunder ecu today and managed to work out how to log my wheel speeds etc but came across an issue im not sure of.

In the setup ive selected di 11,12,13,14 as my wheel speeds which are running off a supra jza80 abs sensors.  3x of them show that the digital inputs are on and active except for di14! Even tho ive selected it as right front speed in the setup menu.

I had the rear up in the air and rear speeds work fine and accurate. Just need to find out why my DI14 states "speed off" ?

Any ideas to try?

P.S. i had the fronts up in air and am getting no speed either (viewing live via logging and spinning wheels by hand).

Tried even another set of sensors.  These same wiring i used on my previous racelogic traction control unit with no issues with all 4x speeds reading, so not sure why this is different!


EDIT: Added my file, please see next post




Edited by Cozcorners
added file
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Ok, I've just tested this.  I do get the same "speed off" indication on DI14, so we have a bug to fix there.  But for me the input still works fine and the wheel speed that you have assigned to that input still displays and logs correctly.  here is a screen shot of your map loaded into a thunder here with 1400Hz going into DI14:



Have you tried taking it for a drive?  It may just be that the low speed when spinning by hand does not generate enough voltage to satisfy the DI signal threshold.


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Thanks Adam.

Ok thats good to know it still works even tho theres a bug(i assumed its not on due to what it stated).

I only spun it by hand, so maybe i cant spin it fast enough like you say.

I'll try over the weekend one day to go for a spin and see what happends.

Thanks again, much appreciated

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Ok, another simple question

There are two sets of wheel speeds i can take to log from! One is the wheel speeds from the "digital input" folder and the other wheel speeds are from the "body and chassis" folder. 

Is there a difference between the two, and if so which one to use for logging? 

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Ok, ive had some success.

Went for a drive and im getting all 4x wheel speed sensors to work and show on my logging.

Some issues tho and not sure whats at fault, so maybe someone can give me an idea what to try?

Rear wheel speed sensors come on fairly early on, around 12kmh, so pretty good.

Front wheel speed sensors however start coming on at about 28kmh! So a bit later then what id like, is there anything i can do or try to bring that sensativity earlier on like the rears?

Once im 28kmh and over, all 4x are nice and smooth and speeds match fairly well to my dash speedo from what i could see at lower speeds.

In the calibration file, i have 2450, i havent tuched this myself so i assume my tuner did, does that sound right? (295/30/18 wheel), and pullup resistor is OFF.  I read the help file and it states usual calibration numbers are 170 to 280...so thats way off.

I did a quick calculations of my diameter which is 0.634meters (295/30/18), and my abs sensor rings have 48 tooth, so.... 48/0.634×31.83 = 2409.8, so the inputed calibration number is not so far off!

Not sure how the extra 50 in the calibration could affect my front sensors picking up speed earlier? Should i try this number?


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The signal strength will be the cause for the delay. You could try making the sensor to wheel gap smaller which should increase the signal strength.

The typical cal numbers are for much lower tooth count gearbox speed outputs.

To confirm the CAL numbers just compare the speed readings with a GPS speed.

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  • 3 years later...

To save cluttering the place up with a new thread...

When feeding an OEM 0-5v speed signal from a 3-Wire speed sensor into DI 13 +, do you have to run DI 13 - to anything or is it still simply a one wire input to DU 13 +?


Thanks for your help guys.

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