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ECU burned Polaris RMK 600 CFI 4 155" 2008

M
I want to share my experience with you all...
The sled was just over 2 years old when I bought it in 2010 and warranty was out. The first ride I had with it, I noticed that all lights was flashing a couple of times and figured it was just my eyes that was wrong... Second ride didn't end that well, in the middle of nowhere it suddenly went dead! Completely, everything! :face-icon-small-sho

After some research i found the fuel filter clogged and it started - yei! I packed my tools and pulled the starter, gave some throttle and off I went for around 50meters... Then it stopped again and some smoke (electrical burned smell) came out. I was so angry that I just started it and ran it over and over again until it went dead :face-icon-small-con
Found the wirings to ECU melted where the ECU is supplied from the voltage regulator. To make a long story short, I towed it down and went to a local dealership with it. Previous owner helped me with this and we managed to get it as a claim :hail:

THE ERROR: Voltage regulator went down and supplied the electrical system with under voltage, causing the ECU to load lots of Amps, which burned the socket and wire to ECU. See picture...
Had to change voltage regulator, ECU and wire harness! Price in Norway was 5000,-USD!!! :face-icon-small-con

I made a solution which will save me for buying a new ECU if it happends again, see pictures. It is easy, cheap and helps your wallet! I use 5 Amps fuses, but are thinking of changing it to 3 Amps.

Since this, it has runned nice :D

ECU Killed.jpg ECU Saver.jpg
 
Last edited:

diamonddave

Chilly’s Mentor
Lifetime Membership
Apr 5, 2006
5,577
3,890
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Wokeville, WA.
First off, you need to change your title to CFI-4.

The CFI-2 was not introduced until 2009. Your's is NOT a CFI-2, it is a CFI-4.

CFI-2's use a copletely different voltage regulator

Second, I commend you for your efforts and it looks like you did a nice job, but this isn't going to do any good to prevent future failures or protect your ECM. I have studied this in great depth and have spent many hours of testing. You need some zenor diodes and also need them on the 12 volt chassis wires. Red/White

My testing has revealed that the VR runs way to hot and then the charging voltage goes up to high. I tested one that hit 19.5 volts. Even the supposed updated voltage reg (it's not updated; simply a new part label sticker over the old one) runs 160 degrees in 10 minutes which is about the same temp of the 1st and 2nd part number VR's.

The other thing you can doo is to install a 12 volt computer fan on top of the VR and relocate the Capacitor.

At least you are thinking and trying...
 
M
My bad, you are correct with the CFI4 - I have corrected it now.

I agree that if overvoltage is the problem, zenerdiods would do the trick. But I find it strange that all my lights did get weaker and not stronger if the voltage increased this much. A peak like that could easily burn a resistans or a transistor etc inside the ECM, and it would be useless without blowing my fuses. However if you have a look at the picture, you can see that it has been a lot of amps present. You will at least save your wire harness :) If I have lights flashing later in the same way, I will change the VR and the Capacitor anyway.

I trusted the "upgrade" of the VR but if it true what you are telling, mabye I should have a look into installing a fan on it. I did not measure temperatures.
Have had any problems after installing a fan?
 

milehighassassin

Moderator: Premium Member
Staff member
Premium Member
Nov 16, 2005
7,464
2,060
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FOCO/VAIL
First off, you need to change your title to CFI-4.

The CFI-2 was not introduced until 2009. Your's is NOT a CFI-2, it is a CFI-4.

CFI-2's use a copletely different voltage regulator

Second, I commend you for your efforts and it looks like you did a nice job, but this isn't going to do any good to prevent future failures or protect your ECM. I have studied this in great depth and have spent many hours of testing. You need some zenor diodes and also need them on the 12 volt chassis wires. Red/White

My testing has revealed that the VR runs way to hot and then the charging voltage goes up to high. I tested one that hit 19.5 volts. Even the supposed updated voltage reg (it's not updated; simply a new part label sticker over the old one) runs 160 degrees in 10 minutes which is about the same temp of the 1st and 2nd part number VR's.

The other thing you can doo is to install a 12 volt computer fan on top of the VR and relocate the Capacitor.

At least you are thinking and trying...


Hey Dave, do you have a thread on this somewhere, or at least saved? I recall the computer fan thread, but don't know much about the capacitor and the zenor diodes.
 
M
milehighassassin - The capacitor is the one located on top of voltage regulator, this you can move somewhere else to fit a computer fan on top of the cooling ribbons of the voltage regulator.
Zenor diods you have to buy at an electronic shop, they designed to the voltage in your system. Example 12V system, they will open and lead to ground if the voltage goes above (approx) 15-16V. This means you "short circuit" your electronic system controlled until the voltage drops below the opening of the zenor diode or the fuse in that distribution wire or stopping your sled.

Hopefully this gave you some input :)
 
S
Dec 15, 2007
418
131
43
Kelowna BC
Your not alone this just happened to my buddies 09 RMK700 .$404 ECU and $144VR.Both out of Polaris good will 1yr warranty.Ouch I am replacing the VR to the new one in my wifes 09 RMK and relocating the capacitor before it happens to me.
 
J
Oct 25, 2019
1
0
1
Hey guys picked up a dragon for a good price. Just wondering if anybody has just put a extra vents in the hood for air flow across the Vr? (Front&Back)
Thanks
 
V

volcano buster

Well-known member
Nov 26, 2007
4,221
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113
Stayton Oregon
I had a similar issue with my 2010 CFI-4 600.

My dealer at the time told me to open up the lower cover and relocate the black box off the top of the VR. For wiring sake, I just turned it over and bolted it through the plastic cover.

IMGP6392.JPG Cap smaller.JPG
 
L
Dec 7, 2007
174
7
18
SWEDEN
My friends ( 2008 ) RMK 600 CFI ( 4-injectors ) just totally burned the ECU :mad:

On the ECU there is 2 different Polaris part #'s

# 4011518
# 4012006

YELLOW coded injectors.

What ECU can replace the one that burn out ?
Can the ECU from the 700 and 800 be used ?
Why does it have 2 different part numbers ?
Which is the latest VR ? Part numbers ?
 
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