Parasitic battery drain Yamaha Neos 4s

[bluntzmastah]

Hello, I have this Yamaha Neos 4s 2009 year ( 4 stroke ) and I am experiencing strange parasitic battery drain. I thought that maybe my battery playing after winter, so I bought brand new one and problem still here.

I tested parasitic drain and it shows 0.058 amps and after disconnecting all the plugs one by one I found that when dashboard and regulator rectifier are both disconnected parasitic drain disappears, but IF ONE of those two ( doesn't matter which one is connected ) are disconnected my multimeter shows drain.



How to fully trace this problems? What next to test?



Thanks in advance.

[bluntzmastah]

update:

I tested rectifier removed and it's all good, where OL it's OL where readings it's stable 0.486V. Tested charging system - idle - 14.4 when accelarating it's about 14.3. So I am assuming charging system works properly.
I re-assembled everything again, and now when rectifiers connected I am getting 0.001 drain reading, and when I plug in dash it goas up to previous readings - 0.054 something like that. I disasembled dash and everything what's inside looks clean as brand new and no burn marks or oxidation, so I am assuming it's alright with the dashboard except that parasitic drain I am having probably from it. :/

It's like 15 wires and 3-4 accesories and I can't trace a problem.

Any ideas? Suggestions?

[snaker]

50 some milliamps isn't a lot.
You could be seeing normal light load systems running in the background: lights, anti-theft, etc
Most cars see that much and a car batt can handle it for months.
Of course, a scoot batt is less capacity, but I would think a healthy battery could handle a couple weeks.
If stored longer, you might disconnect the battery.
Also if extra electrics have been added, the battery may not be getting full charge during run time?

[FrankenMech]

There is a reference voltage divider network in the regulator that draws a little current. All I ever did is use a small battery tender type trickle charger or maintainer on the battery and never had a problem.

NOTE- Don't try to start the scoot with the battery maintainer connected or you will be buying another one...

[bluntzmastah]

The thing is...

Everything was fine, even after staying in garage throughout whole winter ( we have cold winters where I live ) it always started from the first time, no issues at all. And after this second winter something happened. I was able to start it at first, then took it for a short ride and after maybe three days battery dead, recharged it - worked. Then again. So without any tests I just bought a battery and thought that this gonna fix my problem, looks like not. :/ Really annoying tbh...

It's not even a freakin car with tons of accesories / sensors and wires, it's maybe 15 wires in total and only few parts in between, so there should be problem somewhere....

I could install a kill switch for battery or something, but my hands doesn't want to lift up for this job, I'd rather try and eliminate root cause of the problem as it was sitting for months without any issues until now... where I have to recharge every 3 days or so....

[FrankenMech]

Besides the regulator, which is a small drain, it is just a matter of isolation and identifying the drain. You seem capable of using a meter so go to it. We can't do it for you. Otherwise your only option is a shop. In the meantime disconnect the battery to prevent damaging it.

[GrumpyUnk]

One thought for no particular reason: The cluster should not have any draw when the ignition is in the OFF position. Check for battery voltage at the cluster feed. If you have voltage, something on the wiring side, from battery through whatever to the 12v input to the cluster is not right.
A failure of the insulation, something caught between this and that, and connecting where it shouldn't...
It might not hurt to check for V at the heatlight socket with the ignition OFF. If something crossed wires, and is feeding the healight 24X7, it will eat the battery. Some headlights have a smaller bulb inside the reflector, I think used as a marker or parking light, and I do not think it should be powered with the key OFF. Actually, nothing should, AFAIK. Perhaps look at the two wires for battery(the other two are CDI kill and ground, connected in OFF)power feed.  It should not have B+ on both terminals. I think.
tom

[snaker]

Jun 5, 2024 5:28:38 GMT -5 bluntzmastah said:

The thing is...

Everything was fine, even after staying in garage throughout whole winter ( we have cold winters where I live ) it always started from the first time, no issues at all. And after this second winter something happened. I was able to start it at first, then took it for a short ride and after maybe three days battery dead, recharged it - worked. Then again. So without any tests I just bought a battery and thought that this gonna fix my problem, looks like not. :/ Really annoying tbh...

It's not even a freakin car with tons of accesories / sensors and wires, it's maybe 15 wires in total and only few parts in between, so there should be problem somewhere....

I could install a kill switch for battery or something, but my hands doesn't want to lift up for this job, I'd rather try and eliminate root cause of the problem as it was sitting for months without any issues until now... where I have to recharge every 3 days or so....

Confusing: sounds like your symptoms have changed from either dash or RR causing drain to only dash causing drain.
Even so, a healthy batt should last longer than 3 days.
Maybe it's not charging and simply running down till dead?
Maybe a larger drain happens that you haven't seen?
Maybe your test equipment is bad or your misreading?
Maybe the batt is not healthy, even though new?

[bluntzmastah]

GrumpyUnk -> I am thinking of stripping clusters wires and tracing one by one, thanks for insight!
The scooter has ECU, not CDI, but I guess this doesn't really matters? Like mentioned previously I did a parasitic draw test ( watched tons of youtube videos ) and disconnected plugs one by one ONLY LEAVING ONE disconnected at a time and headlight doesn't add numbers to multimeter's readings, but at first it was rectifier playing together with cluster, now after re-assembling, like mentioned beforee rectifier draws 0.001a and the cluster is the one which draws roughly 0.5mA.

snaker -> I have my second battery which is also heatlhy, recharged and tested after a week and it has >13v. The one I bought brand new shows same results. Battery is good. With this amount of drain it is 3-4 maybe 5 days to recharge. I don't ride scooter too often, it sits in the yard more than on the road, and I tested charging. I duno what test equipment should be bad or what should I misread, I have electronic multimeter and I repeated these steps over and over again to be sure. THE FACT IS battery drains over few days without even driving scooter when connected ( you can fully charge battery, put it in the scooter, connect leads and leave it for 4 days and you won't be able to start ) when disconnected it holds charge. With scooter on and multimeter hooked up to battery I am having 14.4V, when accelerating the voltage drops a little like 14.32V something like that, after a longer ride battery is OK, but if the scoot sits for few days batteries voltage drops to the point where I am not able to start scooter. The multimeter reads parasitic drain of roughly 0.55mA which indicates a parasitic drain.
I watched this video: www.youtube.com/watch?v=l20k6vFoz2Y&t=210s and tons of others so I am pretty sure everything's allright. I could suspoect charging system, but AGAIN with the key off I am reading drain of 0.5mA so I am suspecting it has nothing to do with the charging system ( which is also tested ).

I am not electrician nor professional mechanic, but the first readings where rectifier communicated with dash somehow tells me it's something's wrong with wiring/plugs/grounds maybe and just before taking this scooter all apart I am trying to gather as much information as possible.

One thing I remembered now it was some time earlier, after scooter sat for few days, I wasn't able to start it with starter, but I started it from foot ( quite difficult it was ) I then took a ride, but didn't finished it as scooter was misfiring, so I drove maybe km and came back home, I had to push it to last hill lol and my speed was nothing more than 5kmh and it wanted to stall. This was the time I thought my old batt is gone so I bought new, but just before that I recharged old and tested my charging system which also looked OK. Received my new battery -> manual said do not charge -> installed it -> worked like a charm, then after two days same drain re-appeared, then charged my new one, did all these tests I am writing on here and I am where I am now.

[GrumpyUnk]

I have to look closely at my VOM to be sure of what I am reading. I have zero familiarity with ECMs on scooters. Unless they have a KAM - Keep Alive Memory - to store parameters, they should have no need to have any draw at all while at rest.
The numbers acceptable for auto operation is pretty low. A few milliamps once they have 'gone to sleep'. Be sure of where the decimal is when recording amps.
When you had the failure and had to push the last bit, I suspect the voltage was low enough the ECM could no longer operate the ignition/fuel systems. No spark or no fuel will make operation difficult.
I have no clue as to what is going on. I have left non-ECM scooter in the garage and it held a charge for over a month. I did not check for any parasitic drain.
Battery charging will occur if the system voltage is above 12.6v. Lead acid batteries will have 2.1v per cell, multiply by 6 to get 12.6v... As long as your running V is above 12.6 you are charging the battery, limited by the regulator/rectifier. You may have a reg/rec that is faulty, and may be dumping votage to 'heat', or may be intermittently adding a parasitic draw via a questionable semiconductor that decides it is time to become a conductor...
You could disconnect the reg/rec and let it sit for a while to see if it discharges. An ECM system may(likely) have a reg/rec different from the generic in most China scooters. I would not be surprised. It may be the ECM likes its voltage to be more consistent and have less ripple, etc. not an engineer.. of any sort.
tom

[bluntzmastah]

Okay so I've been doing short distances every two days. TODAY I went to about 2km ( started good ), then re-started scoot and came back home again, just before parking I received engine light on the dash with 46 ( I think I checked it correctly ) error code and scoot started missfiring. I tried to start it again, but I wasn't able to do from starter, only from foot. It started and missfired. I'm gonna recharge battery as it's 100 near empty. I am not quite sure it's that parasitic drain causing all this or my charging system is playing?

www.cdielectronics.com/wp-content/uploads/2016/12/M.E.D.S.-Yamaha-Fault-Code-List1.pdf -> this one says OVERHEAT SWITCH.

[aeroxbud]

Code 46 is battery or charging system.