OK, aren't electrical problems fun?! Sorry to be diagnosing this as I go but upon closer inspection of the wiring schematic, service manual and field readings, I got thrown off by them reversing the TPS pin numbering order between the service manual and the wiring diagram (pins # 1 and #3 conveniently change position!). There's also some incorrect photos and references elsewhere on the interweb which isn't helping.

Wire colors are easier to follow:

• TPS Purple Wire must be the ground
• TPS Green/center Wire is definitely the wiper on the variable resistor, i.e. the signal OUT from the TPS that changes with throttle position
• TPS Orange Wire must be the reference signal IN to the TPS (supposed to be 5.0 Volts I believe - I'm only seeing 3.3 V here)

My voltages via back-probing w/ ignition on, throttle closed (not touching pedal)

• Orange to Purple = 3.3V (should be reference voltage to ground, supposed to be 5.0 Volts??)
• Green to Purple = ~0.3 V (should be TPS signal w.r.t. ground, spec is 0.46 V, can change slightly by rotating TPS in housing, voltage increases with opening throttle)
• Green to Orange = ~3 V (reference voltage to signal voltage, not really helpful, voltage difference decreases with opening throttle)

So... can someone please confirm:
1) I should be seeing 5.0 Volts as the reference voltage to the TPS? (ORANGE to purple voltage, key on)
2) The spec TPS setting 0.46 +/-0.3 Volts should be between GREEN and Purple (key on, throttle closed)??

Jeez, I swear last time I set the TPS between the Orange and Green. I think I'm losing it.

If I can regain my 5.0 V reference, I think the TPS signal will come up to near the 0.46 number and I should be OK. In that case I'll be looking for some corroded connection that's robbing me of some voltage at the ECU.

Thanks,
Rob

 

Check the wiring harness behind the seat where it goes around the frame. Its known issue for rubbing thru and causing issues.

 

Does that 5v reference wire go to other sensors? Like, say, a map sensor or something else? If it does, unplug them one by one and see if the voltage comes up. Another sensor could be dragging the voltage down. The other thing you can do is cut the wire at the ecm and see if you are getting 5v coming out of the ecm. I know it isn't ideal to cut the wire but it will let you know if the voltage coming out of the ecm is correct. Use heat shrink tube with glue and solder for wire repairs.

John

 

Alright, I've got enough info now to close this out I think. Hopefully this will saveone else some TPS grief. My 2012 Rzr 800 Service Manual actually explains things more clearly than the 570 manual:

The machine's ECU produces a steady reference voltage of 3.3V to the TPS. It doesn't really state this anywhere though. This particular signal is only going to the TPS from the ECU so I don't know if other sensors are the same (you can back probe the ECU connector if you untape it and poke around). I briefly swapped ECUs with my 800 and it also produced 3.3V. This is between the TPS orange wire (rear-most) and purple (ground, front-most), back probing w/ paper clips with the connector plugged into the TPS, key on, engine off, not touching gas pedal. When powered with 3.3V by the ECU you're looking for a TPS output signal of 0.46 +/-0.03V between the green (middle) and purple wires. This is apparently how the Polaris Digital Wrench works too.

Now, there are special testers that provide their own power to the TPS and that leave the ECU out of the circuit. These would be great to set up the TPS in the throttle body on a bench for example. A common one uses a 9V battery regulated to provide a 5.0V reference voltage to the TPS. In this setup you're looking for an output signal of 0.70 +/-0.05V between green and purple (at idle throttle position).

Mathematically, 0.46 to 3.3 is exactly the same as 0.70 to 5.0 so both of these methods give the same 0.46V signal the ECU will be looking for at idle.

So...

• Orange/rear = 3.3V reference voltage from ECU
• Green/center = 0.46 +/-0.03V output signal to ECU at idle position
• Purple/front = ground with ECU/chassis

My machine's TPS reference voltage was correct at 3.3V and I was able to reset the output to 0.46V while in the machine. It was still idling high/erratically so I removed the throttle body and cleaned it out. Not much in there to screw up but the butterfly had a bit of gunk that may have been preventing it from closing tight. The throttle cable also needed a touch more slack. I also cleaned the airflow sensor with special MAF spray. Reassembled and it idles like a champ so far (1250 rpm). It used to miss a beat here and there before but seems steady now. Hopefully it's fixed but won't be able to tell if it stumbles and stalls again until the next long ride.

 

Thanks for these valuable informations! The TPS on my Sportsman 570 2015 is wired exactly as you said.

In my case, adjusting it to 0.46v with a reference voltage of 3.3v will make it run at 1600rpm at idle. However, I adjusted it at 0.44v instead, which stays in the specs. Now my machine runs well.

Edit: my sportsman ran well, but I made a bad manipulation which changed the tps orientation. So, I had to re-adjusting without knowing the factory adjustment and knowing that it ran well before. Adjusting it to 0.44v made it run like before and the factory's white lines between the TPS and throttle body were well aligned like this.