TPS calibration - not 'seeing' full range

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Plays with cars
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Joined: Thu Oct 01, 2009 5:00 am
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TPS calibration - not 'seeing' full range

Post by Plays with cars »

I've been running MJLJ without load sensing until I got the rest of the powertrain and controls stabalized, now its time to add in load sensing via a throttle position sensor. I've added the sensor onto my throttle linkage and wired it into MJLJ. My problem is that when I use the 'calibrate TPS' feature it only populates a few cells in the values table and results in a choppy % load when moving the throttle from closed to open. (i.e. the gauge only reads: 0%, 16%,33%,50%,66%,83%,100% with no intermediate readings).

I've checked the wiring and all appears correct. The TPS signal into the MJLJ ranges from 1.84V (closed) to 3.86V (open). These values to not correspond to the voltage values that were auto-populated in the load calibration table.

Anyone else run into this issue? Any thoughts on how to resolve it?
Mark Brown
Porsche 914-6, 2.4, MFI, DIS in process

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Post by brentp »

Once you calibrate your TPS, then load value scales from 0-100%. You should then adjust your load axis bins to also range from 0-100% as well.

Once you update that and write it back to the unit, do a power cycle and re-launch the software to double check the settings.

Let us know how it goes!
Brent Picasso
CEO and Founder, Autosport Labs
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