protecting the ECU?

[skibreeze]

Belay my last! I'm sofa king mad right now. I go unload the sled out of the truck and ran it up on a stand. And guess what? Yep it's still lean as hell. So now I'm guessing that the dealer just saw the right voltage and said that it's good to go. I'm 99% sure that it does in fact need the new v.r. and ECU to correct the problem. When I picked it up I was not convinced that a leaking injector was the problem, now this pretty much proves that. The language that I'm thinking right now would get me a few days off from here. WTF can't a dealer actually trust what I am telling them and fix what I tell them it needs fixed?

 

[thefullmonte]

Belay my last! I'm sofa king mad right now. I go unload the sled out of the truck and ran it up on a stand. And guess what? Yep it's still lean as hell. So now I'm guessing that the dealer just saw the right voltage and said that it's good to go. I'm 99% sure that it does in fact need the new v.r. and ECU to correct the problem. When I picked it up I was not convinced that a leaking injector was the problem, now this pretty much proves that. The language that I'm thinking right now would get me a few days off from here. WTF can't a dealer actually trust what I am telling them and fix what I tell them it needs fixed?

I feel your pain buddy. Take a deep breath. I know nothing I'm going to say will help what you are feeling right now, but you can be thankful you at least have a backup sled.
You just described 100% the reason I don't like dealers touching my stuff.
Most of them mean well, but often times fail to put themselves in the customers shoes. Sleds like yours should be getting extra special treatment. They have a history every time they run your vin. And considering you have all the gauges right on your sled they certainly should have caught that. Crix had his entire wiring harness replaced including components. Yours should be getting the same treatment. Poor Cardiac Kid from the other thread too. This is the 3rd year. This is when Polaris needs to send in the big guns for you guys and get this stuff solved.
I think you would have enjoyed the conversation I was having with a service manager this morning. I like this guy and he definitely knows his stuff, but I had to chuckle a bit inside. He is very PRO Polaris, and didn't seem to really want to acknowledge that extent of some of our problems. Really wanted to write off what is being said on Snowest as blown out of proportion. By the time I was done just rattling off a couple of my issues he was very interested in helping me and I wasn't even asking. I appreciate that from him for sure.
He was telling me, "make sure your airbox is firmly seated in the throttle body boots". "They fell off", I said. "What do you mean". "The rubber de laminated and they fell off". His look was something like this He is going to try and get me a new VR.

 

[tree climber]

anybody found anything that works yet?

 

[thefullmonte]

Well, I'm probably going to be running with the plastic electronics cover removed. If I ever get to ride. Double check all your wiring for anything that may be rubbing through. I believe some suspect area's were under the tank and the tail light. Some also reported some concerns of wires rubbing under the electronics cover itself.
I am also adding a ground wire from the common ground on the electronics cover to the black cross brace next to it. Be sure to sand it well for a good contact. I also want to put one from the motor or stator to ground. Haven't worked that one out yet.
And above all it wouldn't hurt to do this.

 

[tree climber]

ha i was hoping somebody had tried the zener idea or something like it and had some instructions. i dont want to be pulling these things out of the mountains

 

[deepdiver]

Well, I'm probably going to be running with the plastic electronics cover removed. If I ever get to ride. Double check all your wiring for anything that may be rubbing through. I believe some suspect area's were under the tank and the tail light. Some also reported some concerns of wires rubbing under the electronics cover itself.
I am also adding a ground wire from the common ground on the electronics cover to the black cross brace next to it. Be sure to sand it well for a good contact. I also want to put one from the motor or stator to ground. Haven't worked that one out yet.
And above all it wouldn't hurt to do this.

Spikes are not detectable by means of an ordinary voltmeter given their brief duration; however they are one of the main causes of faults and malfunctions.

Besides spikes one of the most damaging problems to electronics is HEAT! The voltage reg. along with the ecu have all the components embedded in a ruberized liquid product. This is an old school trick to one hide real cheap components so instead of a 55cent part you have to give someone 120.00. This was a way to keep someone from identifing a circuit...a rather outdated copyright protection. This ruberized poured in liquid does help distruction caused by vibration but adds unwanted heat.

I am going to take a good look at my electronics cage...if the plastic cover isnt needed for any thing other than astectics i will pull it. have to make sure that it isnt a water guard of some type. A taped up thermometer under the cover may give us some good insight to the temps we are dealing with in the electronics area.

Grounds 101..all grounds are not always the same. There are "chassis" grounds and ther are circuit grounds. There are many times where the ground of a circuit is not at the same ground potential as the chassis. Hypothetically speaking you could have a ground of a cuircuit of a few volts and a chassis ground of zero. Addidng a ground to insure the connectivity of a metal chassis part is fine and shouldnt hurt.

Blindly adding extra grounds to sensitive electronics can cause what we call a "ground loop"
In an electrical system, a ground loop usually refers to a current, generally unwanted, in a conductor connecting two points that are supposed to be at the same potential, often ground, but are actually at different potentials. Ground loops created by improperly designed or improperly installed equipment are a major cause of noise and interference. They can also create an electric shock hazard, since ostensibly "grounded" parts of the equipment, which are often accessible to users, are not at ground potential.

In a floating ground system, that is, one not connected to Earth, the voltages will probably be unstable, and if some of the conductors that constitute the return circuit to the source have a relatively high resistance, or have high currents through them that produce a significant voltage (I·R) drop, they can be hazardous.

Low current wiring is particularly susceptible to ground loops.

Our voltage regulators act as a rectifier, smothing, and regulation. Here is a very simplified block diagram of a typical Vreg.


Here is what we have on the second thumbnail

 

[diamonddave]

Grounds 101..all grounds are not always the same. There are "chassis" grounds and ther are circuit grounds. There are many times where the ground of a circuit is not at the same ground potential as the chassis. Hypothetically speaking you could have a ground of a cuircuit od a few volts and a chassis ground of zero. Addidng a ground to insure the connectivity of a metal chassis part is fine and shouldnt hurt.

I can assure you that the engine is not any kind of circuit ground. Polaris' chassis ground is very suspect. Any flexing of that aluminum guard that is providing the sleds entire ground system is a Kapow to the ECM if there is a comprimise in that circiut. Even the doo's I work on are running a ground strap from the chassis to the motor.

 

[diamonddave]

If there's anybody that has a failed Voltage Regulator and or ECM, I'd gladly pay the shipping back and forth for inspection. Unfortunately, I'm sure this would be for a customer pay and not for warranty.

As far as running the sled without the cover, I think you may end up with other issues such as premature corrosion from snow and moisture intrusion among other possibilities. We ran into this on 07 Rev's.

 

[ruffryder]

Are people actually seeing smoke when these go bad? On thing to keep in mind is the ecu will only "take" as much current as it wants. You can't trick it to take more.. so it doesn't sound like a current issue into the ecu per say...

anyone have an oscilloscope and a good and bad voltage regulator? And how about a three phase function generator? Dang I miss the school days.

So anyways, the battery idea is best, though someone said something that the ecu is not at 12 volts but is at 5 vdc? I guess sometimes ecu's use a different voltage for the sensors, but normally the ground and the voltage wire go to the ecu as the ecu controls the voltage, not an external voltage source that the ecu uses.

Interesting problem, kind of reminds me of the issue on the arctic cats where people were removing 100 watts of lights from the hood and blowing their vr as well.

For those that are going to try something with resistors, get some power rating on them. Don't use those dinky 1/4 watt resistors. They tend to act like a toaster after a while of high current usage...

The grounds issue is an interesting one.. I wouldn't think a bad ground issue could effect the ecu and its sensors, mostly because the sensors are generally isolated in their plastic housings and do not have metal to metal contact. Though, deepdiver is right, grounds do some tricky things and floating grounds are really interesting.

What is really weird is the rectifier / regulator going out, and then the sled goes into a lean condition and burns the sled down. I think they got their fail safe operation a little messed up. lol

To sum all this up.
1) Do we know why the regulator / rectifier is failing?
2) Do we know what the output looks like after it has failed? (Need a good one to compare it too.)
3) Do we know what is actually inside the thing?
4) What are the specifications of the sled? Normally there is a listing for the electrical power supply.
5)Do we know why the ecu goes lean? Why the regulator / rectifier is failing in that way?

The nerd in me says some more of these questions needs to be answered before a solution is easily found.

As to the capacitor idea, I am not sure that would work as it really isn't a sink as much as a battery is.

For one of these that has failed, anyone take out the stator and magnet and take a look at it? It might not be a regulator issue at all, but maybe the source is not that good?

dang, sorry for the rant..

 

[tree climber]

seems with as many of these that are going bad somebody would have a bad one that could be tested. i wish i knew more about electric im just hoping one of the really smart people on snowest can figure it out soon

 

[diamonddave]

I chase wires in the auto industry everyday. Anytime there is a popped ECM, 90% of the time, there will be a compromised ground. There are countless TSB's by the vehicle manufactuers for repeat fried ECM's, common theme, compromised ground system. The electrical system in this sled from the voltage regulator on (stator is upstream here) is identical to the automotive systems with the exception of zero ground to the motor EDIT And no fuses!.Go look at any modern vehicle built in the last 20 years, I guarantee you it will have a chassis ground to the battery AND a ground to the engine. You'll find many other independent grounds chassis and motor grounds for the 5 volt sensors.

As far as the ECM's voltage, it runs 12 volts in and the 5 volts is used as reference voltage for the various sensors TPS, BARO, etc. There may be some 12 volt output's but generally ECM outputs will be grounds, 5 volt ref voltage and of course PWM voltage to the injectors.

Disconnect a ground wire on an 05-06 Polaris 700/900 and tell me what happens to the ECM?

Don't ever let anyone try to tell you a compromise in a ground won't/can't cause a problem!! I've seen vehicles where 2-3 brand new ECM's were nothing but dust before i got my hands on them.

ECM's do not like dirty voltage. In fact in many instances (Dodge diesel trucks for instance) I've had to install noise suppressors that would fix wacky electrical noise problems from alternators and cause horrible driveability symptoms. Dodge still continues to try and fix with reflashes. Interference from powerlines, cell phones, alarm systems are all casing issues today.

There seem to be many different symptoms here.

When I get all these other sleds fixed, I'll bring mine in and really dig into this issue. I'd still love to get my hands on some failed ECM's and VR's. I do have a dual trace oscilloscope.

 

[sledhed]

Just going to throw my 2 cents in here as a total layman when it comes to electrical theory, but if some people think there is a short in the tail light wiring under the seat that might be causing a VR problem, or a short in the handwarmer circuit causing the same thing, shouldn't we consider putting a fuse on those circuits to protect against that? (Shouldn't Polaris have put one in? Rhetorical question...) I am no electrical engineer but it seems like a short in those would not blow the VR, but it might make some wiring go up in smoke as everything else drops voltage. But if there is any chance this would save the electronics, it would be worth it, just need to figure out where to put an inline fuse for each circuit...

Edit:
Since the VR is a voltage regulator AND a rectifier, maybe someone needs to figure out how to replace them completely with automotive-grade components that accomplish the same thing... since automotive components are made to handle much higher loads, I would think that would give an extra margin of safety.

 

[skibreeze]

I have an ECU that was replaced with a new one last year. It shows no visable trace of failure. The second failed one shows no trace either. I should finally be getting a new one tomorrow.

Some literally go up in smoke but mine have not. They just start leaning out the motor at any throttle position except WOT.

 

[thefullmonte]

Thanks for the great info guys. I can usually track down an electrical issue, but that is where my knowledge ends. I don't know how a lot of the components really function. So again, thank you guys for the education on components and grounds.
Sounds like I'm still safe to add the ground wire from the electronics shelf anyway. And I don't see an issue with running without the cover. It has holes in it from the factory so items could get wet either way. I have never had an issue and I'm running an Airframe hood. The components under the cover are all parts that used to be mounted elsewhere and exposed to the elements. I feel the cover is purely cosmetic to hide all the wires and give you a place for your belt.

 

[ruffryder]

I do have a dual trace oscilloscope.

can we be friends?? I can get my hands on another one if need be, to check out the signal before the rectifier...

good info on the ground stuff too...

 

[deepdiver]

I chase wires in the auto industry everyday. Anytime there is a popped ECM, 90% of the time, there will be a compromised ground. There are countless TSB's by the vehicle manufactuers for repeat fried ECM's, common theme, compromised ground system. The electrical system in this sled from the voltage regulator on (stator is upstream here) is identical to the automotive systems with the exception of zero ground to the motor.Go look at any modern vehicle built in the last 20 years, I guarantee you it will have a chassis ground to the battery AND a ground to the engine. You'll find many other independent grounds chassis and motor grounds for the 5 volt sensors.


There seem to be many different symptoms here.

When I get all these other sleds fixed, I'll bring mine in and really dig into this issue. I'd still love to get my hands on some failed ECM's and VR's. I do have a dual trace oscilloscope.

Definitely check your grounds...a faulty ground is not a good thing! I like to use the star washers on grounds as they have a better bite all over than a normal split lock washer. When there are multiple grounds stacked on top of eash other I like to use star washers between each on the stack.. I havnt had time to look at the so called infamous Polaris "ground splice" yet.


FYI to all...my dealer showed me an ECU that has just went south for the winter..it was totally smoked..burnt right thru the plastic even. Polaris actually is asking at least this time to have the failed components sent back..normally they dont on these items. Hopefully they will get this resolved...from what I have seen from the melted plastic this could be looked at as a fire hazard with consumer protection groups. A fire next to a plastic gas tank is not a great added value Mr. Polaris.

 

[sledcaddie]

faulty grounds

Another suggestion is to put dilectric grease on the ground terminals. Even the manufacturers use this with pin-connectors. Helps with conductivity and corrosion.

 

[hilinerider]

i pulled the foam from under the electronics shelf to allow it to cool more

 

[diamonddave]

Definitely check your grounds...a faulty ground is not a good thing! I like to use the star washers on grounds as they have a better bite all over than a normal split lock washer. When there are multiple grounds stacked on top of eash other I like to use star washers between each on the stack.. I havnt had time to look at the so called infamous Polaris "ground splice" yet.


FYI to all...my dealer showed me an ECU that has just went south for the winter..it was totally smoked..burnt right thru the plastic even. Polaris actually is asking at least this time to have the failed components sent back..normally they dont on these items. Hopefully they will get this resolved...from what I have seen from the melted plastic this could be looked at as a fire hazard with consumer protection groups. A fire next to a plastic gas tank is not a great added value Mr. Polaris.

Did the VR fail on this particular sled also? I'd sure like to see that thing. What dealer?

 

[mn2mtns]

Maybe this has been discussed earlier but after reading this thread I was under the impression that the plate the VR and other electronics are mounted on should be tied to a motor ground. I did this on one of my sleds and before doing it on the next one I checked it with an ohm meter and discovered that from the factory there is no connection from the top mounting plate to the chassis ground. All components are grounded individually with their wiring. Is there a reason for having this plate not grounded? I checked it on two stock sleds and it was the same, 07 and 08. The wiring diagram also shows no direct ground from the body of the VR to chassis ground and no continuity when checked with the meter. Does this matter? Should it be grounded to chassis and motor or left the way it is?