TPS Adjustment

[Pickwick]

Three months ago I got the FI error on the dash.  After finding and using the diagnostic connector, it was a TPS problem.  I replaced the sensor with the official Suzuki part, but after tweaking the position about 15 times I can't drive more than about 10 miles without the FI light coming on again.  The bike runs fine; I just finished a 450 mile trip with the light on for 440 miles.  My problem is that every time I reset it it's a new setting unrelated to the old one: it's not like turning a carb screw an extra 1/8 turn; every time I loosen the screws I lose the previous setting so have to make a new guess based on where the -C00 is and how quickly the dash resets itself after a small throttle blip.

Apparently our sensor is also used on the GSX250, DL250 and DR300.

I have found in other forums that owners of the GSXS1000 and the Versys 650--and maybe more Suzukis--are using Kawasaki adapter cable 57001-1538 to set their TPSs; costs about $35.  Unplug the sensor and plug in the adapter cable to both connectors.  Then they can measure the actual output voltage of the sensor with a multimeter.  They are looking for a voltage between 1.08 and 1.12.

My questions:  has anyone here done this?  I think their sensor isn't the same as ours, but are the connectors the same?  And if it plugs in, is the voltage the same? 

[Pickwick]

I'll (somewhat) answer my own question:  The cable was cheap enough that I bought one.  No, the Kawasaki cable doesn't fit; the connectors don't match our GW250. 

I am working on something that might be useful:  the cable (and the ECU) measures the voltage through the TPS, but the resistance should be an equally useful measurement.

Unplug the TPS cable and measure the resistance between the middle and upper sensor contacts.  On the bench, my new TPS measures a min of 305 ohms and a max of 4610.  When installed, the sensor travel (ie rotation) is limited by the screws in the mounting slots.  Full CCW (with no throttle twist) is 620 ohms, full CW is 1440.  Somewhere roughly centered is 1140.  With the bike running and the jumper in place, this gave me _C00.  I've tweaked it several times and done test rides.  Currently I'm at 1200 and the F1 light comes on after three to five miles.  It's warmer this week so I hope to do a couple test runs and fine tune it.