PDA

View Full Version : Electronic Start not working


808 Scooter
03-13-2015, 03:10 AM
I'm looking for some help.

I have a jonway 50cc (with bore kit to 80cc). I think the model is Jonway neo. It is an qmb139 engine. 1 year old with 2000 miles.

Not long ago, I had to replace the headlight. After I did that the electric start stopped working a few days later. I can kick start it and it runs fine.

I'm a novice but I've been trying to figure it out. I have found things that were not working well but I still have not solved the problem. I'm fairly certain that it is not the solenoid, starter, or battery. The button for the electric start doesn't seem to work well, but even if I bypass that, it still does not work.

Here is what I can determine.

Current does run to the solenoid but not to both terminals. I replaced the solenoid and have the same problem.

Also, I have noticed that before, when I turned the key, the fuel gauge would come on. Now it doesn't until I get the engine running.

What should i be checking?

bull
03-13-2015, 05:34 AM
Welcome to the forum!

In the thread "Resurrecting a Roketa MC54 250B" I posted a link to a wiring diagram. That diagram is representative of all Chinese scooters I have seen. Get a copy for yourself.
http://scootdawg.net/showthread.php?t=54850

If you don't have any electrical tools, I posted a photo of some tools that are cheap but will work for the casual user.

Here is the way the power flows on the circuit you need: Battery positive --> Main fuse --> Ignition switch --> Chassis fuse (if equipped) --> Brake lamp switches --> starter solenoid coil windings --> start button --> ground

Since I've laid out the power path, you can see IF the brake lights work, everything to there is good. That leaves probing the solenoid leads while the brake switch is depressed for power on both while connected(don't rule out bent pins in the connectors). If that is good, a quick check of the solenoid is to ground the red w/yellow tracer wire with a jumper wire while depressing the brake with key on, if the starter engages, the solenoid is good.

If everything to here is good, then most likely you either bent pins in the right switch harness connector, or the switch is corroded (which does happen). To test the switch, power off, use DMM lowest Ohms setting & probe the red w/ yellow tracer wire to ground (green wire) and depress switch. If it stays high on reading switch is corroded most likely. Those switches can be removed, cleaned and reinstalled w/o replacement.

mmsscooters
04-02-2015, 03:54 PM
you need to check the fuse in the battery compartment, if you turn the bike on and the gas gauge isnt moving you are not getting power

dwint51
04-04-2015, 02:51 PM
yeah most likely your fuse

Back_Slash
04-15-2015, 05:09 PM
Take a screw driver and ground out the terminals on your starter relay and see if that will start it, if so then it's your relay, that's what happened to my jonway.

tvnacman
04-18-2015, 07:04 AM
tell us more about the headlight bulb, how many watt was in there and what did you replace it with?

John

Firehawk989
04-21-2015, 02:50 AM
Also any chance your battery is dead?

tcthomp66
04-24-2015, 12:18 PM
The headlight lamp is actually a good place to start. If the wattage was increased, it potentially could place a higher load on the system and reduce the power to the electrical starter system.

First, check your lamp socket for any corrosion. It can increase resistance, which will lower the output to the starter system.

Second, try removing the lamp and shorting the leads for the lamp together and then starting. If it starts, then your issue is in the headlight area. I would replace the socket and the lamp. (I know this may sound silly -- a lamp is essentially a fuse that provides light. However, I have seen improperly manufactured lightbulbs short or load a system before.)

In the future, there is an old axiom that I hold near and dear to my heart... If it worked before but doesn't work after I made a change, go back and check the change.