Battery light blinking then gets hot
 

I have a 2008 polaris sportsman 500 ho which decided that the battery light would start blinking 20 miles into the trip. Then on came the hot and check engine light. Pulled over let it cool barely turned over. Rode back to truck limping it back. Last stop it had not enough power to turn over. Quick swapped wifes into mine fired right up. Few miles down battery light blinks. Get it home charge battery have it load tested, says it was good. The fan does work when both running and i shut off and turn key but not to start it. I cleaned radiator out carefully with pressure washer, ran it with rad cap off to rid aid bubbles, ive also unplugged heat sensor fan comes right on. Its a carb not efi. Im at a loss. Any help would be greatly appreciated.

While running at an idle check charging back to the battery. Should be between 14-14.5 volts on average. If charging is lower than that,battery can't keep up with current needed while in operation to activate fan and can over heat. The blinking battery indicator is the warning sign somethings wrong. Since you've already tried with two batteries more than likely the ecm is faulty. Controls charging,fan operation along with containing most of the circuit breakers.Item #1 on the parts break down.Dirt Cheap Yamaha, Polaris, Suzuki & Kawasaki OEM Parts & Accessories – Cycle Parts Warehouse http://www.ebay.com/itm/Polaris-4011568-CONTROL-MODULE-SINGLE-CARB-/281486807210?hash=item4189ebd0aa&vxp=mtr Plus leave the radiator cap off,elevate the front wheels and run until fan cycles on and off several times to remove any trapped air pockets than can cause over heating problems also.Top off the radiator and coolant bottle.

So when u say back to the battery do u mean just the battery with a volt meter or is there more to check?

While running,battery should have around 13 volts at an idle or so. When engine is revved up battery should get to 14.5- 14.8 volts according to the manual. If you can't get past 13 volts, then this is not enough voltage to run everything including the electronics,fan,etc. Engines can get hot quickly if this happens. Since you've used two different batteries and it does the same thing,you can rule out a battery problem.The ecm module is what usually faults. You can do a general stator test on the yellow charging wires leading to the ecm module if you wish. All yellows should show a small resistance between each other and NO yellow should short to ground.If this checks out I'd replace the ecm module. Plus here's a cheaper ecm for $171 at Partszilla.http://www.partzilla.com/parts/detai...P-4011568.html

Thanks so much for responding to me. Could you explain in easier terms what exactly i need to test this and what to set stuff to? Also do i use voltage tester and put it to a ground and then the yellow wire? Basic mechanics i am ok with but electronics are a whole new ballgame. Also how is the install of the ecm? Seems like u just take rack off and the front clip under the headlight and should be able to get at it? Do i need to do anything specific to install it?

Yes just remove the front rack,pop the front panel off.Just a simple digital multi meter from Harbor Freight,Walmart,Autozone,etc.. Crank it up,have the meter on dc voltage,check battery reading at an idle,then at around 3000 rpms. Should max out between 14.5-14.8 dc volts if the ecm is charging correctly. With engine OFF,place meter selector on ohms resistance.Pull the connector from the ecm,positive meter lead in one stator yellow wire,negative lead in another one. Should show some resistance reading between all yellows no matter which ones you check. To check for any yellows shorting out,place positive lead on a yellow wire,negative lead to a good ground. NO yellow should short to ground(show 0 ohms) If stator wiring checks out,but charging is not high enough,replace the ecm module. Ecm module just screws on the frame with torque screws,either t20 or t26 if I remember correctly.

I will definitely get a tester and do the tests after the 4th of july weekend. Thanks so much for your time and even helping me find the lowest price ecm if thats what it is. I really appreciated it! I kind of hope its the ecm so i can be done troubleshooting it!

I take it the ECM takes the place of the rectifier on the older models?

Yep and costs 3 times more than a regulator/rectifier since it controls the charging, controls fan operation,has the main circuit breakers,starter lock out,battery protection circuit,hot light indicator control,controls auxiliary electrical among other things.. :)

Ok so heres what ive discovered, batery at it is 12.2 with full charge, at idle slowly increases. i can rev it up and it reaches 13.5. Ive put the multimeter in all yellow wires and if its on the right setting they all show roughly 147 with it grounded. I see .5 when i go each one in a different yellow

.5 resistance between each yellow is fine,so is the 147 ohms to ground.This shows the stator should be ok. 12.2 is low to begin with,fully charged should be around 12.5-12.8 volts. 13.5 volts max is low,will drag the battery down and trigger the battery light especially with other electronics running that take voltage down. Sounds like you need to get a new ecm module.

All right. It drops .7 volts i noticed when i turn the low beams on as well. Plus fan drags it down more. So your really confident its the ecm?;

Best that I can tell you at this point.. If the battery can't keep up,components can't work properly,plus that's why you have the low battery warning light. Plus you've checked the machine with two different batteries if I remember correctly and the results have been the same. If I'm wrong on this you can always have the battery load tested also to remove all doubt that it's the problem.

I did have it load testedand it was good so it must be the ecm. Thank you for all of your answers and your time. Much better then spending the money bringin it in and the wait. Thanks again! Will post when its replaced

Well got the brand new ecm and put it in and having the same issue. Now what?

What's the charging rate back to the battery at an idle then with an idle increase? If charging rate is good,but the battery light shows up on the display,then still could be a several things. Faulty speedo or harness connector(pins not making good contact) causing the warning light. This you can check by pushing,pulling on the connector wiring to see if the pins are tight. Plus could still be a battery. On this I'd have it load tested again just to make sure. Plus if a fan bearing is worn,can place a load on the system. The manual has a load test on it also to see if it takes too much amperage and dragging power down when it kicks on. Or even something simple as the main ground at the engine.

Well with lights on its at 12.0 when fan comes on it drops to 11.5. With nothing on it gets to 12.8. I double checked all the wires to and from battery. Wiggled harness and nothing changed. Wheres the main ground located exactly?

Then it's either not charging(which you can have a faulty ecm out of the box) or the battery or grounds you have are bad. Gotta be one or the other with that voltage.. Neg battery cable grounds to the engine down below the clutch cover a bit. Plus has an engine to frame ground at the top motor mount. Should be a visible ground wire from the frame to the engine.

I cant find the grounds, i got one i see right by the battery on the frame. Do i gotta remove clutch cover would bad fan cause the low voltage if fan's not running yet? Do u happen to live in mn?

Nope I'm in Texas.. :) Just trace the negative battery cable to where it terminates. Make sure it's tight,plus the same on the battery connections,positive and negative and the engine to frame ground on the top right hand side of the engine mount. Plus close by the ecm should be a small group of brown wires. Make sure they're tight. Should either be mounted on the frame or on the coil mounting bolt. Something still is not right when you can't get past 12.8 (battery voltage) and the stator charge coil wires checked out also according to your tests. Plus with the old ecm you got to 13.5 volts. After you take care of any loose grounds,charge the battery over night on a battery tender,than have it load tested. If it checks out,no dead cells then entirely possible the ecm is faulty.Plus don't think I gave you the link to the cheap 5 buck manual. Worth looking at the charging section and wiring schematic.http://polaris-atv.brssm.com/2008-Po...ce-Manual.html Looking at my copy of the manual,shows that if the battery is too low,can't maintain normal battery voltage,the regulator in the ecm has a protection circuit that will not kick on and charge. Something again that makes it worth checking the battery out to see if it's ok..

Brown wires seemed tight, reved it up to 12.7 and it drops to 12 when i turn lights on. This is so frustrating! What are the odds the ecm is really bad from factory? After sitting steady at 12.7 i can rev it up to 13.2. Second fan comes on its down to 12 with no lights on. Would a bad fan cause the drop when its not on yet?

Sound like the battery is dropping,not holding the charge. Charge the battery fully. Then see if the battery starts dropping just using your meter. Possible the battery was/is the problem all along. Plus here's the section from the manual on the charging protection circuit."The regulator takes the output of the 3--phase
alternator and applies it to the battery. SCR’s areused
to connect and disconnect the alternator from the
battery to achieve regulation of the battery voltage.
The regulator circuit produces current on the
BATTERY pin (Pins E & F). If a high voltage transient
is detected on the BATTERY pin this causes the
regulator to assume an open battery condition. The
high voltage transient will cause the regulator to turn
off for a short period of time. If there truly is an "open"
battery(short) then the regulator will remain off as the
minimum battery requirement will not be met. The
regulator will not turn on unless there exists a battery
voltage in excess of the minimum battery voltage
requirement."

The fan if worn(bearings) can cause a drop in voltage if the fan is dragging. The manual also gives you an amperage test on the fan and if shows above a certain amperage before it kicks on,then it should should be replaced.. The manual can show so many tests on different areas and components. That's why I push em all the time on people. First eliminate the battery as the culprit!

Ok so i got the charger on the battery now, i will let it charge all night, then get it load tested. Ill also grab the tester for checking the electrical things from work tomorrow. What should the amps be on the fan and where do i test it?

On testing the fan easier for you to get the 5 buck manual than for me to try to explain.. Plus it has a diagram of how to hook up the meter to test the fan and the amperage allowed.

All right, whats the odds ecm is bad out of box with a "pass" sticker on it?

With what I went through with all the ecm modules,the odds could be 50/50 you got a lemon.. But personally I never got one that was bad straight out of the box myself,but I replaced multiple ecms on the same atvs because they would fail.Again just eliminate the battery as a problem first. If it fails the load test,get a new one and see what happens. If it passes the load test,download the manual and go to the charging section and also the the electrical section that details the fan test.Plus the schematic can help you on the wiring.

Ok had it load tested at a polaris dealer, 12.4 volts on the printout it gave and says good battery.

12.4 is on the low end if that is all the battery can charge up to. Most can get to 12.6-12.8.As long as it passed the load test.Anyway just down load the manual. Go into the charging system tests. If you can't get over 13 volts with two different batteries,two different ecms,then possible the stator itself could be the problem.Plus have someone check directly at the battery with a good meter,don't rely on the speedo for an accurate reading. Plus the resistance tests on the stator charge wires are generally accurate,but not always 100% fool proof. Namely Chapter 10 is what you want to check: Current draw-- Key off, break even charge test, Alternator output test,and charging system testing diagrams.IF all this checks out,then possible you have a bad ecm out of the box.

If you are getting any resistance reading { you said 147 ohms } from any yellow wire to ground you have a grounded stator , it should read infinite { open } from any / all yellow wires to ground with the stator unplugged .

Yep over looked part of that post. Infinity should show OL or 1. depending on what meter he has. The .5 between each yellow is ok.(0.43 +/- 15 %) Possible he's reading it wrong,fingers touching leads??

Mower battery
 

I put a mower battery in my 450 grizzly. Its a 660cca i believe. I use them on my big zero turns and they take more of a beating then when i go mudding on my bike. Thing works great and im working on relocating it again from where i have the stereo equipment to under the seat. If you get one thats not sealed, make a tie down that goes over the caps.