Keep blowing fuses By jburd (Read 9,637 times)

[jburd]

I have a 2007 JCL MP250A scooter with about 600 miles on it. I have had no issues with the scooter so far and love riding it. Yesterday however I took the scooter on a ride and it died in the middle of the road. The starter button wouldn't do anything but the dash was lit up. I attempted to use the remote start after which everything went completely dead.
After some digging I figured out I had blown both fuses in it - the 15a fuse next to the battery and the 20a fuse on the starter solenoid. I replaced the fuses and went out for another ride. Got about a hundred feet away and it did the same thing. I didn't use the remote start this time and the 20a fuse didn't blow. However the 15a fuse did. I have replaced 3 15a fuses so far and cannot figure out what is causing them to blow so easily.
I thought it was an issue with the rear break switch because it seemed to happen when I was coming to a stop and pressing the brake handle on the left. Didn't seem to happen when I used the front brakes only. I can't however get it to do it when I am in the driveway and pressing the rear brake switch.
Does anyone have any ideas?

[JR]

First of all welcome to the forum! Now the 250A is the carbon copy of the 250B and I own both and the faster RED ones!

There are 4 versions of this scooter as far as the wiring diagrams go as of to date that I know about and on this link your version is the second one the linhai;

thescooterprofessor.proboards.com/index.cgi?board=250g&action=display&thread=430

Now the red wire on the starter relay that has the 20A fuse goes to two places the key igniton switch and the remote/alarm. The 15A fuse by the battery is on the black wire from the key switch and it feeds all of the accesories like horn, brake lights, turn signals, radio, CDI etc.

With the 15A fuse blown or removed the scooter will still start with the remote because you are still sending 12Vdc to the system but if the 15A fuse is blown you'll not have any accesories. Know this sounds crazy but the remote alarm system is just a electronic key switch and is on ths same circuit as the manual switch. Now the remote again will start the scooter if the 20A fuse is good. If the 20A fuse is blown the scooter is totally dead.

Now fuses blow for one reason, amp overload. This could be caused by a very bad connection or a short.

The fuse holders are to say the least poor and that the first place I would check. Make sure the fuse is getting a good connection, if it's suspect go to the auto parts and get a replacement socket and change it out.

Now it's also sounding like a wire that's rubbing when you move the scooter and it's almost got to be the black wire off of the key ignition, again it feeds lots of things including the CDI which is located right by your battery. The black wire feeds it too. If it is the brake circuit only when you press the brake blowing the fuse then the wire that comes off of both brake switches is the yellow/green and it's shorting out in the system.

If it's not the fuse holder then it's time to open her up and lets go through the harness and find the gremlin. We're here to help.

JR

[jburd]

I've heard of the remote start causing issues. Can that be disconnected?

[JR]

Yes and the thing is on the left side behind the headlight cowling, got to remove the front ot get to it. Just unplug it and it'll cause you no issues then.

But my gut feeling here is you've got a wire rubbing and shorting out. If you remove the front then I would take the time to go through all the electrical connections like in our extensive PDI says and make sure this will not happen again.

Whether you bought it new or used a very through PDI will keep you riding and enjoying it instead of pushing it.

We're here to help keep us informed.

JR

[jburd]

So I got the front off. Started looking around at all the connections. Haven't looked at everything but there was a bare wire in the black wire coming off of what appears to be the left speaker. There are 2 of these in there - one on the left and one on the right. I can't believe that would cause the major issue but I'll keep looking.

[jburd]

I went over the entire wiring harness and didn't see any issues. I even reconnected the battery and started the scooter. I went through every connection in the front with the motor running hoping it would short something out while I was touching it. Nothing shorted out. I have unplugged the remote start since I don't use it that much and don't really NEED to use it. I have read elsewhere that some guys have had a lot of issues with that unit and it kept blowing fuses. I'm going to look at all the back connections as well. I'll keep everyone posted if I find anything.

[JR]

Great and while you're tracing the wires keep in mind the black wire and if you suspect the brakes trace the green/yellow also. Now to really look at the harness headed to the back you need to remove the belly cover over the gas tank. You'll naturally see a large wiring harness covered with a spiral looking plastic tube cover. You can untape it save it and check the wires.

In this harness will be a multitude of wires and some split off to other sections of the scooter. They are nearly always put together with brass crimp clamps or may be soldiered. They are always poorly wrapped with a little piece of tape and they have been known to come apart or the tape come off and rub. In this same harness is a network of green wires and they are ground wires, if the black or green/yellow is uncovered and touching a green even only for a second you'll pop the 15A fuse.

Myself I re-work these connections and then properly cover them with liquid tape or heat shrink. If you don't want to mess with the brittle Chinese harness tube cover go to Walmart and buy a bag or two of harness spiral wrap, easy to put on and makes a great harness cover and if needed in the future easy to remove.

Also do trace out the black wire to the CDI it is the 12Vdc power source as this scooter uses a DC powered CDI.

Hang in there you'll find it. BTW the black wires to the speakers is not the problem.

JR

[damin69]

Also check really close around where the wires are zip tied really tight around the steering triple tree. I found that there is a cover of the bearing on mine that had a really sharp edge and the wires were pulled so tight up against it that it cut through the insulation of the wires and until I cut the zip tie i did not see it even then it was hard to see.

[jburd]

This has been crazy. I got everything down to basically the frame. I have the wiring harness all opened up. I have gone through every wire and connection that I can see and I still haven't found anything that convinces me what the issue is. There was one wire going to the carburetor that had the clip on it broken exposing the wire. I have fixed that. Not sure if that is the issue or not. It has been so tedious and time consuming getting everything taken off, I am leery of putting it all back together without knowing that I have it fixed.
Can you explain a little what the CDI is? I'm not sure what I am looking for. There are 2 black boxes in the back above the muffler. A lot of wires come out of them. Is that the CDI? Sorry if I am asking dumb questions, I am just new at this.

[JR]

Not dumb questions. That's how you learn. Here is the CDI;



It is located generally under the seat in a little pocket strapped to the side behind the battery.

It will have 5 wires:

green = ground
yellow/black = feed to coil
gray/white = engine kill wire
red/white = pulse signal wire from stator
black = 12Vdc from key switch

Check all of these wires especially the black one to be sure they are ok.

The boxes you mentioned on the side are the regulator/rectifier (R/R) and blocking diode;



The blocking diode cannot cause this issue. The R/R has 6 wires to it and one of them is black. It ties into the black off of the key switch. Check all these wires especially the black wire to make sure they good.

After I went through all thses wires I would then start her up and move wires all around to see if you can make it short out.

Also Damin made a very good suggestion about checking the wiring harness good around the steering tree, lot's of owners have had trouble there.

JR

[alleyoop]

Yep, there are never DUMB questions if one does not know, how else is one supposed to learn if you do not ask, what is this, what does it do etc.. Knowing those answers to parts helps to find a problem with a system. Otherwise one can spend a lot of money replaceing parts that are good until the bad one is replaced. Sometimes though it is more than one part that is causeing a problem, you replace the bad diagnosed part and find you still have the problem but it may be the next part in line that was masked by the first part being bad.
Good Luck Jr will get you rocking and rolling
Alleyoop

[jburd]

First of all thanks for all the help. I appreciate all the support. I have been a member of lots of forums and seriously have gotten a ton more help in a shorter period of time here. Hat's off to you guys. There is a ton of good information here.

Here's what I have done. I went ahead and replaced the fuse holder. Figured it didn't hurt since I already had it open and it only cost about $3. I went through the wiring harness and removed all of the small pieces of electrical tape around all the little splices and redid them with liquid electrical tape. Again a cheap step that couldn't hurt and could potentially help with a problem I couldn't even see. I went through all the wires in the steering tree. I did find a green wire that appears to come from the kill switch that had a section of its coating rubbed off exposing the wire. Tried to short it out by touching it to something with the engine running. Couldn't get it to short anything out but figured it would probably cause some issue and could be the problem either way. I coated it with liquid electrical tape. I also have unplugged the wireless starter. Thinking about moving that to the glove box where I can plug it in but can easily get to it if it causes problems in the future. I think I'm going to put it all back together and hope for the best. I can't find any other issues in the wiring. If it still is a problem my thought is it would probably be a component like the remote start, the regulator, the starter solenoid, or possibly the brake switch.

Lastly I bought a 12v plug to be able to power up a gps or charge my phone while driving down the road. Was planning on putting it inside the glove box. Will that work and if so where is the best place to wire it in? Thanks again!

[damin69]

I put my 12V outlet in the glove box and ran 12 guage wire all the way back to the battery to power it with an inline fuse on one. Then I put a fuse block in my other one in the glove box.

[JR]

If you plan on using it a lot I would do like Damin said and be sure to put a inline fuse on it.

JR

[jburd]

It's all put back together and I took it around the block several times. NO ISSUES!!! I think in retrospect it was either the fuse holder for the 15a fuse or the remote start or both. There were several wires that could have possibly been the issue. I don't really know. In the end it was good to spend the time to meticulously go through it all. I did move the remote start to a place where I can plug it in without having to take the front off again.
I did run the wires from the front to the back for the 12V plug and hooked it up in the front when I was putting it all back together. I didn't hook it up yet in the back until I get the inline fuse but at least it's there and that's simple to do.
Damin just to clarify, should an inline fuse go on both the positive and negative wires? Thanks again everyone for your help. Very much appreciated.