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Discussion Starter · #1 ·
First time poster here and I need help. I am trying to find info about the asm sensor/T.P.S., such as what it does and how it affects the sled if it is not working. I am tying to pin point a problem in my sled. Thanks.
 

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well what kind of problem are you having my sled is causing the temp light to come on and causing a det prob which i havent figured yet is that whhat yours is doing
 

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tps problem

throttle position sensor what problems r u having and what sled is it my sled has one it adjust position of throttle from idling 2 screws usally hold them on and u can loosen and adjust
 

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My sled is is a 2003 Polaris XC600SP. IT starts fine and idles good, but between 6000-7500 rpms the sled stumbles as if the carb is loaded up. If I let off the throttle and get back on it hard and get the rpms up to 8000, it will pull like crazy and run great, but I can't run wide open all the time and if I let off a little bit it stumbles again. I cleaned the VES and it didn't help, so I am wondering about the TPS. I need more info about the ASM sensor/TPS as to how it works and symtoms if it is not working. Thanks.
 

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tps problem

sorry cant be more of help mine is a 1995 650 efirxl r u shure this is the problem there is a way to test them at idle and full rpms with a tester a guy has one on youtube im shure someone on here can help keep us posted to see what u find out:dunno:
 

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Discussion Starter · #6 ·
sorry cant be more of help mine is a 1995 650 efirxl r u shure this is the problem there is a way to test them at idle and full rpms with a tester a guy has one on youtube im shure someone on here can help keep us posted to see what u find out:dunno:
I am not sure this is the problem. I am just trying to narrow down and rule out possible problems. This is my first sled with a TPS, so i would like more info on how they work. I have done numerous searches and can't find any good info.
 

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The TPS should be factory set and not require adjustment unless it has been removed or replaced. There is a factory test kit, Polaris part no. 2201519, but there are some home remedies using parts from Radio Shack. Basically, you input 5.0 volts into the tps and measure voltage coming out. At wide open throttle, voltage out should be 4.0v to 4.2v. You will need a good digital meter to test. After the voltage is set to spec, use an analog meter to determine if there are dead spots in the TPS. You can have proper voltage at full throttle, but as you open the throttle, the analog gauge will show if you have bad spots in the TPS.

If you take a trip over to www.snowest.com and search there, there are diagrams and part numbers on how to build your own tester.

Here's a link to the Snowest info, you may have to join the forum to access the page.

http://www.snowestonline.com/forum/showthread.php?t=67427


If you have a good relationship with your dealer, they may throw their tester on your sled for free. It's a 5 minute process, especially on the Edge sleds.
 

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Discussion Starter · #8 ·
The TPS should be factory set and not require adjustment unless it has been removed or replaced. There is a factory test kit, Polaris part no. 2201519, but there are some home remedies using parts from Radio Shack. Basically, you input 5.0 volts into the tps and measure voltage coming out. At wide open throttle, voltage out should be 4.0v to 4.2v. You will need a good digital meter to test. After the voltage is set to spec, use an analog meter to determine if there are dead spots in the TPS. You can have proper voltage at full throttle, but as you open the throttle, the analog gauge will show if you have bad spots in the TPS.

If you take a trip over to www.snowest.com and search there, there are diagrams and part numbers on how to build your own tester.

If you have a good relationship with your dealer, they may throw their tester on your sled for free. It's a 5 minute process, especially on the Edge sleds.
Thanks BC_Dan, I will try to test or get this tested and let you know what I find. I am a person that likes to know how things work and what they do, so I am still wanting more info on the TPS and how it functions with the motor.
 

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my sled is an 04 800 edge xc and when i first start it up the temp light comes on and flickers for about 3 min or so then after that it runs fine so its not a temp prob it seems to be a det problem. i have disconnected all sensors but it still flickers only on start up. could this be a tps problem. thanks
 

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thanks bc dan i will test that but i am still curious why this light comes on and then after sled warms up it runs fine. nothing has ever been touched on the sled and this prob has just started one day when i started the sled. could this tps be the problem do you think and thanks
 

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It could be a temp sensor problem. Those are known for breaking wires inside the insulation and not working properly. The only time I have been around a TPS related problem was on an RMK 900, a friend had issues on a ride. His symptoms were poor running, hesitation, ran like garbage after 4 miles. It ended up the overflow hose on the coolant bottle had fallen off, the bottle was over full and was squirting antifreeze into his TPS. It may be worth taking the TPS connector off the carbs and making sure the contacts are clean, then reseating the harness. Can't hurt to make sure you have good contact.
 

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I had one that the wires were frayed, on close examination, you could see the break.

"TEMP LIGHT TEMPERATURE SENSOR TEST (2002 Polaris manual)

The temperature/warning switch is normally open.

1. Set the mulittester on the ohms scale
2. Disconnect the lamp wire
3. Connect one test probe to the switch terminal and the other to engine ground. The meter shoujld show an open circuit. This indicates a normally open switch. If the switch were heated to approximately 205 deg. F. the contact in teh switch would close and the reading would be less than 0.4 ohms.

If attempting to heat the sensor to close the contacts, heat only in a water bath. Never subject the sensor to an open flame to attempt to close the contacts as sensor damage will result."

The temp sensor works with the ECU and the TPS to retard timing when an overheating condition is detected. The hotter things get, the more aggressive the ECU is at retarding timing until the "limp mode" is encountered.
 

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Thanks BC_Dan, I will try to test or get this tested and let you know what I find. I am a person that likes to know how things work and what they do, so I am still wanting more info on the TPS and how it functions with the motor.
XC, it didn't look like you had your question answered to your satisfaction. The TPS is simply a potentiometer (or variable resistor). It's exactly the same concept as a dimmer switch on your living room lights: as you move the dimmer more open, the lights brighten, and as you close it, the lights dim, all in a very smooth, linear way.

Functionally, there are three wires connected: a ground, a source of 5vdc, and an output. The 5vdc is connected to a wound coil, the output is connected to a sweep arm. As the sweep arm moves from one end of the wound coil to the other, the resistance lowers, and consequently (Ohm's law) the voltage rises. The sweep arm is connected to the throttle body and the throttle, so as you open the throttle the sweep arm moves.

To test, you would connect an analog meter to the output (and ground), supply 5vdc to the source line, and slowly open the throttle. The voltage should very slowly and steadily rise as you open the throttle. If you stop mid-open, the needle on the meter will hold at the same voltage.

Over time, things can cause the wound coil to become contaminated, and when the sweep arm starts encountering contaminated locations that it loses contact on, the voltage will drop. You see this on the analog meter very easily, as quick drops of the needle. Digital meters do not show this very well, it's best to use an analog meter when looking for something like this.

The EFI computer reads the TPS output, along with a bunch of other sensors, to determine how much fuel to spray into the throttle bodies. These contaminated spots on the TPS can cause the EFI computer to overreact, causing very extreme drivability issues and dangerous behaviors of the engine, from a rapid drop to a rapid increase in engine speed. A bad TPS should be diagnosed and replaced ASAP.

Actually, here's a really good article about the TPS. It's really meant for a car, but all TPS work the same. You can actually skip what I have already written if you like, I'm leaving it here because I took the time to write it and am not about to throw it all away.

Symptoms of a Bad Throttle Position Sensor | eHow

Hope this helps!

Alex
 

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02 xcsp 600, I have also changed the temp sensor on mine for the same reason that was mentioned. mine, the wire started pulling out of the sensor..
 
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