I have a 2007 Polaris Sportsman 500 efi. The other day I went to start it and when I turned the key to on, I got nothing, no display, nothing. Then while waiting 10-15 seconds the display would come on and the fuel pump would make a clicking sound. Then the display would go out again, then come back on after 10 seconds and fuel pump would click again. It just keeps doing this over and over again. The only time I have power to anything is when the display comes on for a second or two. I can jump across the solenoid and it turn the engine over just fine but it won't start and there is no power to anything. I had a previous 07 sportman 500 efi that did the same thing and I replaced the ecu under the headlight and then it worked fine. I'm wondering if this atv is having the same problem of a bad ecu. My question is there anyway to test the ECU or PDM before shelling out the money for a new one?


It sounds just like the problem discussed here. http://forums.atvconnection.com/pola...laris-atv.html

 

If you've eliminated any connection or ground problem and the battery is good,it does sound like an internal circuit breaker in the ecm module could be tripping and resetting. It's functions for charging and fan operation plus has several internal circuit breakers. We've had to replace a few of these. Bad location to begin with,plus isn't sealed well enough to keep out moisture.I remember some electrical gurus posted about tearing into this module and posted that they were able to repair some problems,but can't find the posts on this. Could be worth a shot as this module is close to 400 bucks. Item #11. Dirt Cheap Yamaha, Honda, Arctic Cat & Polaris OEM Parts & Accessories – Cycle Parts Warehouse
Here's a 5 buck pdf manual if you don't have one that I believe does have some tests to help you isolate the problem. http://polaris-atv.brssm.com/2007-Po...ce-Manual.html

 

Thanks Old Polaris Tech. I purchased the manual. I'll do some reading and hopefully I can find an answer. I don't know if there is a fault code that would tell me anything, although I can't do a "blink code operation" because the speedo power won't stay on but a second or two and then shuts off and then back on 10 seconds later. My previous ATV was the same year and model as this one and it did the same thing. When I replaced the ECM or ECU, it worked fine. I remember back then that I bought both PDM and ECM modules. Replacing the PDM did nothing. It wasn't until I replaced the ECM that it fixed the problem. I am curious to know if a bad PDM can cause the same symptoms of power tripping on and off over and over to everything (speedo, efi, lights, etc) as a bad ECM?

 

The pdm works the same as the ecm on carb type models as to its functions. Polaris throws the term ecm/pdm and ecu together a lot unnecessarily. Yes the "pdm" or ecm module,not just the ecu or "brain box" as many call it can cause this problem. Internal shorts or internal circuit breakers can cause power to be shut off from the rest of the machine.Like mentioned,we replaced a few pdms on atvs and also Rangers that had the same problem as yours, no power to the dash,speedo or ignition in some cases.

 

On my last polaris 500 efi, I replaced the brain box/Electronic Control Module (ECM) under the headlight and then it worked. Replacing the pdm behind the radiator did nothing that time. This is what the service manual says about troubleshooting the ECM. "For the purpose of troubleshooting, a known-good ECM from a same-model Polaris 500 ATV EFI may be used without system or engine component damage." That's well and good if you have a spare 500efi ECM lying around.

My thought is to bite the bullet and shell out $400 for a new ECM seeing that is the part that was bad in my last 500 efi. I wish there was an aftermarket ECM like there are for the 700 and 800 efi's.

I wonder if Polaris redesigned the ECM to fix the problem of them always going bad?

 

Before you spend some more $ open up the ecm/pdm and see if it looks like this one that's been water damaged.

 

It had 300 miles on it and shows no signs of water on the outside and I've never had it in the water or pressure washed it. I hate to crack open a good ECM module, and then find out it has a bad PDM. I wonder if they are able to reflash a bad ECM, or if that is even an option if its bad.

 

The cost of each module is about the same price,over $300. This is where Digital Wrench would take the guess work out of which one is bad.A good shop would usually charge you 1 hr labor and in a case like this on efi machines well worth it imo rather than guessing and come up wrong.

 

I just wanted to correct what I posted earlier. It is the PDM that went out on both of my 500 efi's. So if anyone has the same symptoms, look at replacing the PDM that has aluminum fins and is located behind the grill.

 

I had the same exact issue with my 06 sportsman. So came into the house and found this thread, went back out and unplugged the ecm the terminals were very clean I just cleaned the grim from around the external portion of the connector. She started right up. hope this helps someone -AF