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it may very well be cause this is the updated ecu #4011599.
 

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I don't see any recalls or bulletins
 

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Model Name - SPORTSMAN700EFI,RED/BLK
Model Year - 2007
Model Number - A07MH68AZ
Purchase Date - 4/9/2007
VIN - 4XAMH68A27A207690
Engine Serial Number - 0120326904400
Factory Warranty
Start Date - 4/9/2007
Expiration Date - 10/9/2007
Extended Service Contract (ESC)
Start Date - N/A
Expiration Date - N/A

Product Recalls
Check and review status’s of safety recalls on your vehicle.
Number of Recalls: 0
Last Updated: 3/26/2020
  • There are no found recalls for your vehicle.
 

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whats the issue OP? do you think you have a bad ECU?
 

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Discussion Starter #8
Every time I hit the throttle I loose all spark. It will idle all day long.

Fuel pressure is good.

I reset ETC switch, nothing happened. The interesting thing is it's like the ETC switch doesn't even work. I can make the switch touch and it will still idles like nothing is wrong.

The Etc switch tested fine, no wires shorted where the plug connects.

If I hook up my meter to the black wire at the Etc switch it shows continuity is good at the Ecu plug on the black wire.
But it also shows continuity is good between the black etc wire and the two colored coil wires in the Ecu plug. I don't know if that should happen.


I can't find any shorted wires, which makes me think the ecu could be bad.
 

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and the shitty thing is the only way to find out if the ecu is bad is by swapping it with a known good one.
 

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OK - the black wire does kill the engine when grounded - I would find the BLACK splice where 5 black wires are junction-ed together and separate all the black wires - this should eliminate being able to kill the engine, then check continuity to pin 25 of the ECU plug and all 5 wires - the one wire with continuity is the kill wire of the ECU the other 4 wires go to; the key switch, the handlebar switch, the throttle switch and the speedometer - try accelerating the engine with all the black wires disconnected - if it revs normally, connect one of each of the 4 wires to the wire going to the ECU and try to accelerate the engine - when you find the wire that causes the engine to die trace it to the device it goes to and adjust or replace the item it is connected to. If the engine dies when you try to rev the engine with all the black wires disconnected from the ECU - test for spark, if it sparks wile the engine dies it's fuel and not electrical. Done
 

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Brown is ground - black is kill - connect the black wire of the ECU to ground and it kills the spark - disconnect the black wire of the ECU from ground and if it sparks, the ECU is good and you just have to find where the black wire is connected to ground - if disconnecting the black wire of the ECU does not restore spark, then you have to fully troubleshoot the ignition system.

Now, you have spark because it will idle, right? And when you open the throttle it dies, right? If it's not the throttle switch, and it is not the key switch, and it's not the handlebar switch, that leaves the reverse limiter which is in the speedo, but the speedo is tied to the stator - if it's the reverse limiter causing the problem, holding the reverse override button in while opening the throttle should allow it to accelerate and you only need to determine why the reverse limiter (speedo) is cutting spark.

So if you eliminate all ways to kill the engine and it still dies upon opening the throttle, then the problem is either fuel or a component of the ignition system which is ECU, pulse coil, or primary coil.

Process of elimination :unsure:
 

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Discussion Starter #19
Brown is ground - black is kill - connect the black wire of the ECU to ground and it kills the spark - disconnect the black wire of the ECU from ground and if it sparks, the ECU is good and you just have to find where the black wire is connected to ground - if disconnecting the black wire of the ECU does not restore spark, then you have to fully troubleshoot the ignition system.

Now, you have spark because it will idle, right? And when you open the throttle it dies, right? If it's not the throttle switch, and it is not the key switch, and it's not the handlebar switch, that leaves the reverse limiter which is in the speedo, but the speedo is tied to the stator - if it's the reverse limiter causing the problem, holding the reverse override button in while opening the throttle should allow it to accelerate and you only need to determine why the reverse limiter (speedo) is cutting spark.

So if you eliminate all ways to kill the engine and it still dies upon opening the throttle, then the problem is either fuel or a component of the ignition system which is ECU, pulse coil, or primary coil.

Process of elimination :unsure:
I tried holding in the reverse override switch test, to test that circuit and see if the problem would go away. Nothing happened.

If I barely press the throttle I can get the rpms to come up a bit.
 

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Is there a plug on the throttle switch? If so, then unplug it and try accelerating - if it still dies, unplug the speedometer and try revving the engine.
 
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