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engine light on
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paulf
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paulf
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gts250 ---My manual labels a light on the display as the "engine management and injection fault indicator light" but doesn't tell me what it means if the light goes on.
It goes on while I'm driving, but goes out when I stop at a light. I'm assuming that this is something that needs attention. Am I safe in driving until I can have it looked at?
Anybody know more specifically what this light tells me?
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stickyfrog
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MP3 250 and 2 MP3 500s
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stickyfrog
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MP3 250 and 2 MP3 500s
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Location: Nashville, Indiana
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Classic symptom of a bad voltage regulator. Check this wiki article to see about testing for it. MP3 250: Removal of the voltage regulator
Quote:
Symptom
Engine light comes on when rpms increase and shut off at idle. Help from people on this forum indicated that this was a classic symptom of a voltage regulator (VR) failure.

Testing
Using a multimeter I was able to verify that it was indeed a VR failure. At idle the voltage across the battery terminals was 14v and at 4000rpm it climbed to almost 19v. Since it should never go over 14.6v this indicates VR failure. Running a PTW in this state would quickly ruin the battery.
Do not ride with a duff VR. It will fry your battery.
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paulf
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thanks very much for your reply. very helpful
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stickyfrog
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MP3 250 and 2 MP3 500s
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Location: Nashville, Indiana
 
stickyfrog
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MP3 250 and 2 MP3 500s
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Posts: 22659
Location: Nashville, Indiana
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Thanks for posting and welcome to Modern Vespa.
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