What Tests Can I Do Before Replacing Yamaha Grizzly ECU?
Before you go spending money on a new ECU for your Yamaha Grizzly ATV, you should first run some tests on the starting and charging systems to see if the problem lies elsewhere.
Partzilla’s Yamaha ATV expert John Talley livestreams Q&A sessions on our YouTube channel every Friday at 3pm Eastern. In this session, John was asked what testing should be done before replacing the ECU on a 2009 Yamaha Grizzly.
Yamaha Grizzly ECU Testing Q&A
Before I order a new ECU for my 2009 Yamaha Grizzly, is there a test sequence that I can perform? I wait a day and it does the same thing, turns on and shuts down. What now?
John Talley: There’s a whole lot of testing you need to do before you jump in and replace an ECU. Because out of all my years — and there have been a lot of those — very seldom is the ECU the problem. I mean, 99.9 percent of the time it’s something else. You didn’t really give me anything to go on as far as what the “same thing” is, but I can tell you don’t just jump out and buy another ECU. You’re going to be disappointed, because it’s going to end up being something else. Now, what can it be? A whole bunch of different things. It could be fuel starvation, or it could be something to do with your electrical system or the charging system. Or it could be the ignition system. There’s a lot going on other than the ECU telling it not to run anymore. But why? So I would hold off on that and go test all of your systems … once you’ve eliminated all other possibilities, whatever is left is usually the answer. You haven’t eliminated all the possibilities, or at least you haven’t sold me on it yet. Not in that simple question that you gave me. Give me some more information and I can help you walk through this.
Watch the video below to see how to test the starting system on a Yamaha Grizzly ATV.
Watch the video below to see how to troubleshoot problems with a Yamaha Grizzly ATV that won’t turn off.
Watch the video below to see how to test the charging system on a Yamaha Grizzly ATV.
Want to see more live repair questions answered? See more motorcycle and ATV repair questions answered here.
