ECM voltage supply issue

[pura vida]

so aksnowrider help me check/set my tps last night, thank you every much, as it was off and is already idling better. need to make my own tool now. snowing too hard and the light is to flat to going out today for testing... don't you just hate it when that happens!

but.... we did find an issue. but i'm not sure how big of one it is. when checking/setting the tps we (ie. mike) first checked the voltage coming from the ecm to the tps. polaris says this value needs to be between 4.99 to 5.01 as it is a 5 volt system. mine was 5.08. that is obviously out of spec but how big of a deal/much of a difference is that going to have. compared to the spec that is way out but taken by itself it seems to be rather insignificant? opinions? thoughts?

pv

 

[crashnbash]

.07 volts is not a whole lot. I bet if you check it with a different meter you will get a different result.

 

[poliguy]

there is no replacement for a good quality meter.

 

[icr]

Knowing Mike I'd assume he was using a high quality meter

 

[xc6rider]

That value wouldn't bother me.....

 

[AKSNOWRIDER]

.07 volts is not a whole lot. I bet if you check it with a different meter you will get a different result.

there is no replacement for a good quality meter.

I use a Fluke 88 meter..made just for automotive electrical systems..and about as good as you can get in multi meters...its acurite..
Cory..I will be doing some checking on this but my guess right now is most likely the ecm is pooched....07 of a volt doesnt sound like much..but on reference voltage..its important...Reference voltage is used not just for the tps..but most all sensors..so it affects all sensor outputs....

 

[diamonddave]

I wouldn't worry at all about the extra .08 volts. I see this in the autofield all of the time for 5 volt reference's swinging up to .15 volts each way. That extra .08 volts can change depending on engine load, RPM's, and charging system loads ie lights, hot grips, etc.

I think you might be hard pressed to get Polaris to warranty your ECM due to an internal 5 volt driver running a tad higher voltage unless you were having a runnability symptom. Run it.

 

[AKSNOWRIDER]

Dave, I would agree..but polaris is pretty specific that it must be between 4.90 abd 5.0 volts...I would bring itto the attention of my dealer and let them hash it out with the dealer...This is straight off the dealer site online manual for 10-12 pro ride chassis.......

Cleanfire Fuel Injection
4
9923311 - 2010-2012 PRO-RIDE RUSH/Switchback/RMK Service Manual
© 2011 Polaris Sales Inc.
TPS Tests
Two tests can be performed to quickly determine if further testing is required.
TEST 1: TPS Idle Voltage
1.Connect Digital Wrench to the vehicle. Confirm the throttle lever free play is set to specification, and the throttle cable is not pulling on the throttle plate cam.
2.Click on the DATA GRID ICON to view the current sensor readings.


3.Locate the TPS VOLTAGE reading and compare it to the specification for the vehicle. Verify SENSOR REFERENCE VOLTAGE is 4.9-5.0 VDC.


TEST 2: TPS Signal Sweep
Utilize the sensor graph function to view the TPS voltage return signal voltage as a line graph.
1.Slowly move the throttle lever in and out. The return signal line should change without any erratic jumps or gaps.
2.If erratic jumps or gaps are encountered, inspect the wiring, and connector pins at the sensor and ECU connector.
3.If no wiring problems are found, inspect the TPS to verify it is securely mounted to the throttle body. If loose, it will have to be readjusted.
4.Replace the TPS if steps 3 and 4 do not resolve the issu

 

[AKSNOWRIDER]

Also of concern this is the third pro I have checked..and at .720 is the closest to spec..but still out by quite a bit on base setting voltage(polaris spec .690 to .710 volts), all 3 sleds were dead on at .930 for idle voltage spec and both mine and the other sled were dead on at 5.0 volts reference volts...

 

[pura vida]

thanks mike, let me know what you hear. i just thought i would throw it out there and see if anyone else had something similar or other experiences. i'll run it by the dealer and see what they say. hopefully i'll have a chance to do some "testing" this weekend. i have no idea what effect .08 of a volt will have on the sled but i really don't think this is going solve my missing hp issue. but i'll be sure to fully test it... it not like the thing is running like crap.

pv

 

[AKSNOWRIDER]

thanks mike, let me know what you hear. i just thought i would throw it out there and see if anyone else had something similar or other experiences. i'll run it by the dealer and see what they say. hopefully i'll have a chance to do some "testing" this weekend. i have no idea what effect .08 of a volt will have on the sled but i really don't think this is going solve my missing hp issue. but i'll be sure to fully test it... it not like the thing is running like crap.

pv

I honestly dont think the .08 of a volt is going to be an issue either..but for sure let polaris decide..yeah I doubt it will be a cure all either..but I think it will be better..let me know..

 

[xc6rider]

Are you checking these values at idle?

Just wondering, cause at idle has many different meanings to different mechanics, and many in a shop atmosphere forget a key component.....warmed up!

At idle, per most manufacturers, would mean warmed up to full operating temps, and idle adjusted to within maybe 100 +/- of specs. And for testing, this can be very important, and can have big fluctuations on testing. Lots of little things that can cause a electrical difference in testing, and easily overlooked in a "shop" setting.

From my experience, very few electrical components have fallen right inside specs, and like mentioned, unless you see a symptom, nothing will be done.

Voltage tests tend to fluctuate more than resistance tests, and are especially more dependent on set rpm's, so I tend to worry less with voltage tests.


Not trying to discredit your testing.... I'm sure you probably did them correctly, just adding in my experiences.

You just never know with some of these mass produced components anymore. Some may test out perfectly normal, yet swapping them out may make a night and day difference in runability! Unfortunately, it's very expensive, if not impossible for a consumer to swap out parts for a fix, and sometimes all you can do as a mechanic....

 

[crashnbash]

Xc6rider brings up a valid point about the enviroment. Even something as simple as the temp of the wires can affect the readings. A circuit with a high temp will show a higher resistance than a circuit wilth a low temp.

 

[mountainhorse]

To me ... .08 volts seems significant enough.

But there are a lot of different factors that could affect the readings.

To me... If it IS off by .08 volts, and the factory specifies that this is 4.9 - 5.0 and the Digital wrench program goes out to three (4) decimal places (eg 4.990 etc)... I'd say that 80% of spec variation is significant if above the upper threshold.

The first thing in the TPS testing procedure from the factory is to check the TPS ref voltage.

TPS Tests
Two tests can be performed to quickly determine if further testing is required.
TEST 1: TPS Idle Voltage
1. Connect Digital Wrench to the vehicle. Confirm the throttle lever free play is set to specification, and the throttle cable is not pulling on the throttle plate cam.
2. Click on the DATA GRID ICON to view the current sensor readings. 3. Locate the TPS VOLTAGE reading and compare it to the specification for the vehicle. Verify SENSOR REFERENCE
VOLTAGE is 4.9-5.0 VDC.

I'm sure it is frustrating if/when Polaris tech/engineers read these posts.

On one hand, if the customer has a problem they want to know what is going on.
On the other, the factory does not want a lot of backyard mechanics getting in there and finding a problem that is not really there. (not saying that anyone on here is... I know that Mike is extremely qualified to check this type of thing out)

If your dealer is feeling friendly .. they will let you watch while they run it on Digi Wrench for the same test.

 

[diamonddave]

I still stand by my original statement. XC6rider and crash also make very good points about how temps affect resistance values, voltages, etc..


Mike, when you tested for the 5 volt reference signal, did you try testing the ground circuit from a different ground to see if there were any differences? Does it change (5 volt ref) without the TPS connected? Did you try changing hot grip settings, brake lights on/off, revving engine up some, different coolant temps, etc. to see if there was any differences? I'd be curious if it changes trying a different ground and different electrical loads. The other question I have is the idle voltage of the TPS any different when checked on the sled versus when you adjust and set the TPS with your TPS tester?

I haven't been under the hood deep into the Pro yet so I don't know how well their ground system is but I do know that it was/is a joke on the IQ-Raw's. Additional ground wires could help. I've also grounded circuits that were supposed to be grounded by modules on full time grounds. Noise in an electrical system can also cause things like what you are seeing. And the IQ has a very noisy electrical system. Noisy electrical systems always raise hell with potentiometers, can you say Cummins Diesel?

The reason for the spec of .690-.710 volts is to allow for variance's just like you are seeing here.

This is why it would be better to adjust the TPS with the ECM's 5 volt refernce signal and a Digital wrench or good multi meter than using a seperate 5 volt tester with the 9 volt battery.

 

[AKSNOWRIDER]

great points dave sled was warm from cory unloading it, pulled into a room temp garage and checked..everything was hooked up including the tps (as per polaris procedure ) when it was checked(I have fluke pin testers that are designed to slip into the back of a connector without damage)..I did not check grounds, just noted reference volts and factory settings...this is the third sled I have tested in the last couple weeks..everything done exactly the same...the other two both had exactly 5.0 volts on reference line...now I will say this ...the reason manufacturers use 5.0 across the board for reference volts is to do away with 99% of these issues..it is that important that it is precise..hence a low output battery/alternator wont drastically affect reference volts since the ignition will normally stop firing long before you get that low on volts..as to adjusting it using the engines own ref signal(running) you could..but the vibrations of the engine running would make it about 10 times more difficult to do..I have set cars and trucks this was but they isolate the vibrations so much better then a sled that it is doable..still faster to do it with a tester I think...Cory is going to run it by the dealer and see what they and polaris say..my guess is polaris will put an ecm into it..and cory's sled isnt running as good as last season(had to drop 2 grams in the primary to run the rpm he did last season) so this could be a part of the issue...

 

[AKSNOWRIDER]

Are you checking these values at idle?

Just wondering, cause at idle has many different meanings to different mechanics, and many in a shop atmosphere forget a key component.....warmed up!

At idle, per most manufacturers, would mean warmed up to full operating temps, and idle adjusted to within maybe 100 +/- of specs. And for testing, this can be very important, and can have big fluctuations on testing. Lots of little things that can cause a electrical difference in testing, and easily overlooked in a "shop" setting.

From my experience, very few electrical components have fallen right inside specs, and like mentioned, unless you see a symptom, nothing will be done.

Voltage tests tend to fluctuate more than resistance tests, and are especially more dependent on set rpm's, so I tend to worry less with voltage tests.


Not trying to discredit your testing.... I'm sure you probably did them correctly, just adding in my experiences.

You just never know with some of these mass produced components anymore. Some may test out perfectly normal, yet swapping them out may make a night and day difference in runability! Unfortunately, it's very expensive, if not impossible for a consumer to swap out parts for a fix, and sometimes all you can do as a mechanic....

X, from years and years in the automotive side of fuel injection(my first classes were way back in 82 when gm first released electronic fuel injection, plus numerous other classes over the years) every ecm I have been around from stock gm,ford,chrysler,well crap you name the manufacturer i am sure i have worked on it at one time or another...all the way to stand alone race stuff every ecm I have ever seen will hold a consistent reference voltage from 10 volts to over 16 volts(on a 12 volt system), its just how the manufacturers build them because that reference voltage is so important..I am hoping others on here(mostly dealer techs) will chime in and keep track of what they are seeing when they check them....I cannot stress the importance of those wanting to buy a meter and test/set their own on how critical a good meter and proper method is to do this..if you even feel a little leary checcking/setting this..dont..take it to the dealer..and say..please..I have some beer here for you boys..can you humor me and check my tps settings..even if its with digital wrench it will at least give you a rough idea of if its in the ball park...

 

[pura vida]

"tested" today. (pretty much epic conditions and good light an hour or so) no real change. it is idling better after adjusting the tps so that is good but top rpms are still the same, as expected. went over to hpp (local dealer) and talked with them although i didn't have the sled for them to plug in. after discussing i'm going to bring it in next week and have them plug it in to see what if any codes pop up. trying to figure out where the heck my hp went that i had last year. have eliminated the easy/cheap stuff. even picked up new spark plug caps. will try those next time out. don't think that is i but otherwise i'm down to ecm, pistons, or injectors. all of which are fairly expensive. although the injectors are "only" $100. i did a compression check and they both matched at 115 which seemed low but i know it can vary from tester to tester. plus they were both the same so that is the more important thing. wouldn't think they would both go bad at the same time. i just wish something would fail so it would be easier to figure out. right now it runs pretty good but just doesn't have the power that it did last year. although there seems to be a few strange runability things that are starting to pop up but nothing that is consistent or real obvious.

pv

 

[diamonddave]

great points dave sled was warm from cory unloading it, pulled into a room temp garage and checked..everything was hooked up including the tps (as per polaris procedure ) when it was checked(I have fluke pin testers that are designed to slip into the back of a connector without damage)..I did not check grounds, just noted reference volts and factory settings...this is the third sled I have tested in the last couple weeks..everything done exactly the same...the other two both had exactly 5.0 volts on reference line...now I will say this ...the reason manufacturers use 5.0 across the board for reference volts is to do away with 99% of these issues..it is that important that it is precise..hence a low output battery/alternator wont drastically affect reference volts since the ignition will normally stop firing long before you get that low on volts..as to adjusting it using the engines own ref signal(running) you could..but the vibrations of the engine running would make it about 10 times more difficult to do..I have set cars and trucks this was but they isolate the vibrations so much better then a sled that it is doable..still faster to do it with a tester I think...Cory is going to run it by the dealer and see what they and polaris say..my guess is polaris will put an ecm into it..and cory's sled isnt running as good as last season(had to drop 2 grams in the primary to run the rpm he did last season) so this could be a part of the issue...

Sure it is but if you are having problems, it's a good idea to know these things for sure than to start throwing darts, I mean parts at it.

I think much more testing needs to be done before an ECM is replaced. When I was talking about checking for reference volts and idle volts on the sled and using a different ground and checking for voltage on the grounds, I was talking more about just energizing the ECM with the engine off although checking this stuff with the engine running can be and should be done also to make the diagnosis be more conclusive. Sure it's a little more difficult but nothing is easy in life. That's why it would be nice to test the 5 volt ref without the TPS connected. Is the load of the TPS being plugged in causing a fluctuation in Ref volt? Could be...maybe not.

So how did you check ref volt? Was engine running or system energized?

What is your full throttle TPS volage?

Is it possible the lost RPM's might not be worn pistons like we see in the CFI-4's?

I think my first class tickets would be good for this one.

 

[AKSNOWRIDER]

reference voltage done as polaris does with DW..everything plugged in /sled idling..
i never checked full throttle reading dave..just not a factor for me everything is controlled based off that closed throttle plate setting...I did check for a dead spot in his tps though...the only way a tps would change ref. volts I think would be some type of internal short..
I guess I will have to bill cory for those first class tickets....but you are buying all the booze while your here, and I am inviting all my drunk buddies over the whole time(alaskan drunks make canadians look like non drinkers buy the way)...