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Discussion Starter #1
Hey All,

Newbie RS1 owner here, lastnight took the newly purchased RS1 out for its first ride and i noticed something that kinda concerns me, but unsure how to understand it.

When i looked at the vehicle before purchase, i stuck a jack under the rear to lift it and tested to see if the front would pull the vehicle in Low Gear, but i never thought to test it in Hi Gear. Lastnight i was riding in an area that had very soft sand, so i flipped 4WD on after coming to a stop, shortly after that i got stuck and noticed ONLY the rears were turning. The fronts were not even acting like they wanted to turn. Confused i stuck it in Low Gear and immediately i got unstock with the fronts pulling me out.

Is this normal? I was under the impression 4WD would work in both Low and Hi gear. My buddies Ranger works in 4WD hi... So i am confused.
 

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Are you sure you were stopped? I know I've hit the switch going too fast before and the 4WD didn't engage until I turned it back off, came to a stop, then turned it back on. It won't engage above something like 12mph, even in high.
 

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Old Dirt Bike Rider
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Are you sure you were stopped? I know I've hit the switch going too fast before and the 4WD didn't engage until I turned it back off, came to a stop, then turned it back on. It won't engage above something like 12mph, even in high.
Computer won't engage front drive until below 3,000 rpm or something like that.
 

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Discussion Starter #6
TY for the manual section, i put the rear on the jack, stuck it into Low, activated AWD and it engaged as soon as i take off, pulling the bike on the jack with the front wheels. As soon as i shift to High Gear while stopped, nothing changes on the dash except gear change, but only the rear wheels spin and fronts no longer do anything with AWD switch STILL turned on. I switch back to Low gear and it will pull forward with front tires...

It seems like the process of shifting to High Gear is somehow disabling the AWD system.
 

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Aspiring Perfectionist
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Wow.... that would have to be an ECU problem then, sounds like it's pulling the ground signal to the front diff when you shift into H, like it thinks you're in neutral or park. I would definitely suggest taking that back to the dealer for warranty.

Does it work in reverse? What about if you are already in H, and then flip the AWD switch on?
 

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Discussion Starter #8
Wow.... that would have to be an ECU problem then, sounds like it's pulling the ground signal to the front diff when you shift into H, like it thinks you're in neutral or park. I would definitely suggest taking that back to the dealer for warranty.

Does it work in reverse? What about if you are already in H, and then flip the AWD switch on?
Hmm i didnt try reverse when i was out testing it. I will have to try that out.

I tried doing it in H both ways out of AWD and turning the switch on while stopped, and also going into H with AWD already turned on from L.
 

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Aspiring Perfectionist
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Yeah, that's not normal man, I would take that in to the dealer for warranty work unfortunately.
 

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Aspiring Perfectionist
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And of course it “worked fine” for the previous owner right? Or it just skipped his mind?

You can bypass the ECU sending the ground to the coil in the front diff without causing any problems. You’ll just have to remember not to flip the switch with the rear wheels spinning. Hess motor sports sells a bypass switch, but you can also build one fairly easily if your familiar with wiring at all.

Try this:

Unplug the front diff ( check engine light will come on for the time being ), and run wires directly from your Acc and Gnd terminals on your busbar to the pins on the diff plug, doesn’t matter which goes to which pin, as long as they’re not touching each other, then test function on the jack again.
 

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Do you know if the ECU has been reflashed and if by who one of the other guys will know more about this but that issue may be resolved by sending it out and having a programmer check it out.


Sent from my iPhone using RZRForums.net
 

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Discussion Starter #15
Well i can conclude the issue i am having is not the front differential, but that probably there is a short or bad ground occuring on the electrical path for High Gear not allowing the magnetic system in the front differential to function properly. I have read a bit today on how the AWD system on our vehicles work and its actually a pretty cool little system. Very mechanical and less electronic than i thought.
In this video he explains it very well by actually showing you all the parts of the differential, he just doesnt explain it FULLY clearly enough.

So how the system work is there is ALWAYS movement inside the front differential via the driveshaft powering the pinion gear on the differential ring gear.
Inside the center of the Ring Gear is the Hilliard Cage with ramping groves machined for the roller bearings of the Hilliard Cage can spin within.
On the outside of the Hilliard Cage is the plate that slots into the Hilliard Cage called the Armature plate.
When you activate the AWD system on the Polaris, it starts to compare the readings of the trigger teeth on the Armature plate to the rpms of the rear wheel Armature plate.
When there is enough of an RPM difference between the front and rear wheels, it activates magnets in the cover which acts like a magnetic brake on the front Armature plate, causing it to rotate the roller bearings inside the Hilliard Cage into the ramp portions of the inner differential ring gear, thus acting like a ratchet in a way only allowing the wheels to be locked together in a single direction. As soon as you roll backwards, it falls off the inner ramps allowing the front wheels to free ratchet, but as soon as you apply more rpms to the rear it ramps the roller bearings back into the ramps, causing the entire front differential to lockup and apply power to the front tires.
658528


658529
 

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Aspiring Perfectionist
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If there was a short, or bad ground in the AWD circuit, you would be getting a check engine light, and it would not work in Low either. Your problem very much seems to be that the ECU doesn’t register H gear, or, as stated above, is tuned to not allow 4wd in H gear, which would be really strange.

Try wiring it direct like I stated above.
 

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Yes, I know where we are?
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For your information, this is incorrect:
, it starts to compare the readings of the trigger teeth on the Armature plate to the rpms of the rear wheel Armature plate.
When there is enough of an RPM difference between the front and rear wheels, it activates magnets in the cover which acts like a magnetic brake on the front Armature plate, causing it to rotate the roller bearings inside the Hilliard Cage into the ramp portions of the inner differential ring gear
All the armature does is suck up to the armature plate and slow it down which rotates the roller cage into position so the rollers can lock.
 

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RWB713
I have not looked at brake down of the trans but is there any way It would not turn the prop shaft in H but due to a different set of gears being used for low that would engage the prop shaft and allow the AWD to work in low only


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RWB713
I have not looked at brake down of the trans but is there any way It would not turn the prop shaft in H but due to a different set of gears being used for low that would engage the prop shaft and allow the AWD to work in low only


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No, the driveshaft turns in all gears.
 

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So how the system work is there is ALWAYS movement inside the front differential via the driveshaft powering the pinion gear on the differential ring gear.
Inside the center of the Ring Gear is the Hilliard Cage with ramping groves machined for the roller bearings of the Hilliard Cage can spin within.
On the outside of the Hilliard Cage is the plate that slots into the Hilliard Cage called the Armature plate.
When you activate the AWD system on the Polaris, it starts to compare the readings of the trigger teeth on the Armature plate to the rpms of the rear wheel Armature plate.
When there is enough of an RPM difference between the front and rear wheels, it activates magnets in the cover which acts like a magnetic brake on the front Armature plate, causing it to rotate the roller bearings inside the Hilliard Cage into the ramp portions of the inner differential ring gear, thus acting like a ratchet in a way only allowing the wheels to be locked together in a single direction. As soon as you roll backwards, it falls off the inner ramps allowing the front wheels to free ratchet, but as soon as you apply more rpms to the rear it ramps the roller bearings back into the ramps, causing the entire front differential to lockup and apply power to the front tires.
View attachment 658528
There are no "trigger teeth" or sensors in the diff, after the ECU energizes the coil (ground side) the lockup is 100% mechanical.

As RWB said if it works in L & R and not H there is a problem with the ECU or the gear indicator. Does it have a tuner or has it been reflashed? Under some conditions a tune can mess up the AWD settings in the ECU. Does H appear on the display when you shift to high? Possible the gear indicator on the trans is not sending the correct signal to the ECU.
 
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