Electrical frustration By stevensonrc (Read 604 times)

[stevensonrc]

Hey all I purchased this 2007 sunl 250-22 last year. It had run well, if a bit rough, for most of last summer, and this spring. It was a bit finicky at first but after an oil change, new spark plug and radiator flush it seems to be running well except for the cooling fan. I gave up on the heat sensor that plugs into the radiator, after replacing it with out any change, and installed a witch bypassing the sensor under the seat. Recently it quit during a ride into town. I had gone perhaps a half of a mile when the darn thing up and quit on me. It was running smooth then when I pulled up to a stop at a one lane bridge it was running one minute then the next dead. The engine quit all gages died no indication of power. I have currently tried the following:

1. Trickle charged over night
2. Replaced the starter coil
3. Replaced the solenoid
4. Replaced all the fuses & fuse box

Nothing changes. I turn the key and no power. I replaced the ignition coil, and the solenoid no change. I noticed if I put a jumper across the solenoid the starter tries to crank, but it doesn't quite turn over. I noticed when I replaced the fuses that some of the wiring between the wiring harness and the fuse box was melted, so I replaced the furze box. I am still not getting any electricity to the starter or the gauges. If some one could give me their opinion as to if I should replace the entire wiring harness or the cdi box and if I should try to find a sunl part or use a rocketa instead, as most of these are basically the same scoot with different branding.


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[JR]

Welcome to the forum Stevensonrc. Sorry that you're going through all this but I'm betting we can fine the trouble. Also some of the things you replaced are a good thing and you've kind of already gave an insight as to what is wrong.

The replaced fuse box with the melted wires indicates amp or current overload and/or a short.

If the fuse box is the typical on like on most of the CfMoto clones (linhai version has no fuse box) then it is broken up into 4 circuits.

One of the circuits is for the lights only so we know that's not it. But the other 3 run off of one single wire and that's the feed wire from the ignition key (usually a black wire) which would include the brake light circuit.

Now the brake light circuit is also tied into the starter relay (solenoid) and if the brake lights don't work then nither will it start. The brake light circuit (usually green/yellow wire) feeds the positive side of current to the starter relay.

When you press the starter button then you supply the negative side of the circuit to the starter relay. It's made thjis way so you have to have a brake on to start the scooter.

Now the single small wire from the battery (usually red) has a 15A fuse and if it's blown then nada no power no start.

Now you may already know but if you don't then you need to find out why the melting wires? Also if you jump the solenoid and it just barely turns over then you've got one of 4 things

Bad battery, must be at 12.5 Vdc or better
Bad wire connections in the starter circuit (red wire cable from battery to solenoid)
Bad starter
Engine in a bind (you said it was acting finicky?)



Replace the harness? Nope you'll not find one that matches, fix the one you have.

You need to turn the key on and get your volt meter out and see if you have any voltage from the battery to the key switch and if so then find out if you have power going from the key to the fuse box.

JR