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Warning light
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frank webster
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frank webster
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The engine management light keeps coming on while riding then going off when slowing down and stopping. Could someone shed some light on this please. Thanks
@safis avatar
SaFiS
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1979 P150X, 1983 P200E, 1987 PK125XL Elestart, 1988 T5, 1995 PX200E, 2011 Yamaha Fazer 600 S2
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SaFiS
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@safis avatar
1979 P150X, 1983 P200E, 1987 PK125XL Elestart, 1988 T5, 1995 PX200E, 2011 Yamaha Fazer 600 S2
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Location: Veria, Greece
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Could be overcharging from a bad regulator…
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wbdvt
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Molto Verboso
'16 Sprint S 150, 2 x '06 GTS 250, '12 GTS 300, '74 Vespa 150 Super
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wbdvt
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'16 Sprint S 150, 2 x '06 GTS 250, '12 GTS 300, '74 Vespa 150 Super
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It would help to know the year, model, mileage of your scooter.

When you say engine management light, is this the check engine light?
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frank webster
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frank webster
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Yes it's the check engine light On my 2010 GTS 250 with 18520 miles
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wbdvt
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'16 Sprint S 150, 2 x '06 GTS 250, '12 GTS 300, '74 Vespa 150 Super
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wbdvt
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'16 Sprint S 150, 2 x '06 GTS 250, '12 GTS 300, '74 Vespa 150 Super
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ok, if the CEL is off at idle and then comes on when riding, most likely the VR.

Best way to confirm is with a voltmeter. Measure battery voltage with scoot off at battery terminals, should be 12.8V or a little higher

Start scoot and measure voltage, should be greater than 13V and less than 14V

Rev scoot to ~3k rpms, measure voltage. If goes higher than 15 or so, bad voltage regulator
Positive
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frank webster
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frank webster
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Thanks for the info wbdvt👍
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wbdvt
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Molto Verboso
'16 Sprint S 150, 2 x '06 GTS 250, '12 GTS 300, '74 Vespa 150 Super
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Location: Vermont
 
wbdvt
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'16 Sprint S 150, 2 x '06 GTS 250, '12 GTS 300, '74 Vespa 150 Super
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Report back on your findings
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BUGGSY
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GTV / GTS, 1961 Lambretta LI Series 3
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Location: Somewhere on the Island of Great Britain, East Coast, Last time I looked.
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wbdvt's got it, I would do this test first to see if the voltage regulator's thrown a wobbly.
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