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Stator / Regulator or Connector? Error 46 and drained battery, Dash and bike died!

1873 Views 9 Replies 2 Participants Last post by  NorthCust
Hi everyone, bought the worlds worst/abused 2012 R125 as a first bike, built it up and repaired a lot over the last four months, thought I was there and now this (although I think the error was there I think just undiscovered...anyway). Its had an intermittent code 46 error but I though it was initially due to the battery originally in it being knackered.

I put a new battery on the bike as it had a bigger (physically) battery that had the tray mashed up to make it fit by the previous owner, stock spec gel battery put in along with a new lower section to replace the battery tray. since the rebuild and after the crappy weather it had a first run Friday...all good but error 46 came up again, only out for 30 mins. Went out again today and 10 minutes in the dash went off then the bike died. Basically battery flat. would jump off a jump pack and then die very shortly after being disconnected.

After pushing it home for two and a half miles (that was good fun) I've put it on charge and the meter is ready so start testing stuff in the morning. So my question is, are there regular failures with something on the charging circuit with these bikes to look for first (connector block corrosion or loom damage) I'm hoping its not the stator because I really don't want to pull that engine casing off again!!!

Cheers

RockingDad
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have you got a multimeter? If so - check the voltage across the battery terminals with ignition off (shoudl be around 11.8-12.8 when charged), and when running (should be about 13.6~ volts)

If the voltage is not higher when running then your charging circuit has a problem.

If the voltage is low with the ignition off (e.g. 10v) and you've just charged the battery, then you may have a dead cell in your battery, though that would be unlikely on a new battery unless it was perhaps left on charge all the time since you got it or has been damaged some other way (idk what).

If your engine-running voltage is not higher as it should be, imho first thing to check would be just inside the left-hand side of the frame, about where the subframe starts and where the weld-seam is on the main frame spars. on the inside there's a thing bolted to the frame (rectifier i believe). That has a plug going into it from the underside (3 pins iirc). If that's not plugged in properly, or has corroded contacts, that would mean your charging circuit isn't happening and would give you that sort of running-flat along-the-way type issues as you describe.

If that doesn't work then I'd perhaps be looking at contacts in the plug which comes out of the stator etc. I'm not sure what the voltages are supposed to be on those plugs but it'll be in ther service manual.

Btw if you don't have a copy of the service manual... obtain one. There's pdf downloads to be had online (for gen1 anyway).

Voltmeter across the battery terminals should tell you what's going on tho :)

hope that helps.
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have you got a multimeter? If so - check the voltage across the battery terminals with ignition off (shoudl be around 11.8-12.8 when charged), and when running (should be about 13.6~ volts)

If the voltage is not higher when running then your charging circuit has a problem.

If the voltage is low with the ignition off (e.g. 10v) and you've just charged the battery, then you may have a dead cell in your battery, though that would be unlikely on a new battery unless it was perhaps left on charge all the time since you got it or has been damaged some other way (idk what).

If your engine-running voltage is not higher as it should be, imho first thing to check would be just inside the left-hand side of the frame, about where the subframe starts and where the weld-seam is on the main frame spars. on the inside there's a thing bolted to the frame (rectifier i believe). That has a plug going into it from the underside (3 pins iirc). If that's not plugged in properly, or has corroded contacts, that would mean your charging circuit isn't happening and would give you that sort of running-flat along-the-way type issues as you describe.

If that doesn't work then I'd perhaps be looking at contacts in the plug which comes out of the stator etc. I'm not sure what the voltages are supposed to be on those plugs but it'll be in ther service manual.

Btw if you don't have a copy of the service manual... obtain one. There's pdf downloads to be had online (for gen1 anyway).

Voltmeter across the battery terminals should tell you what's going on tho :)

hope that helps.
Thanks for your reply bud, your video on taking that side of the engine apart on YT helped previously with refitting the pulley key which I found in the oil pan when servicing from the previous owner. Stator turned up and I swapped it out and all good now, thankfully the regulator was ok because that looks like a total pain ITA to remove and replace. Just had the MOT today and failed on several things so yay some new projects, main one being adjusting the steering head bearing which has excessive wear or free play.... this bike is really fighting me to restore it to the road!

Cheers :)
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oh nice! glad it helped :)

If you don't have a copy of the service manual def start there. Adjusting the head bearing sounds worse than it is.
Update incase anyone find this thread through a search... The replacement of the stator in this instance resolved the problem.

Cheers for the assistance

Dualboot
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Glad to hear you got it fixed :)

So I guess in this instance you would have got the same voltage reading across the battery with the engine running as with it switched off (or very close anyway). In any case it wouldn't have been higher when running, which would have indicated that there was a problem with the charging circuit, which would then mean check the rectifier and stator..

Did you take readings or just replace the stator and then it worked?
I took voltage readings at the battery with nothing on or running, then took readings with the engine running....still the same 12 volts (battery was drained due to no charging circuit).

I then took off all the necessary left side fairings and located the white plugs that feed from the regulator/recitifier and the position sensor, cleaned them up then tested with engine running again...still no charge (should be around 14v at about 5000rpm if memory serves).
Then tested the stator with a meter at the white plug (three pin) I'd just cleaned.. readings were way low at about 0.1 ohms so knew I had a failure, should have been around 0.47 I think.
Then unplugged the rectifier plug and tested that using a guide on YouTube, that tested fine so isolated down to the stator.
Ordered a new stator and case gasket, drained oil, swapped stator (fairly straightforward) but make sure you test it before you swap it as I've had faulty new parts before and it's no fun stripping something down again when you can bench test it first. I put it all back together, fired it up and....no change... arghhhhh.... then after about a minute of running everything fired into life, 14v at the battery and everything is good and has been ever since!
You'll also need some threadlock for the bolts that hold the stator on the case.

Cheers

Dualboot
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oh good stuff working through it like that and thanks for the explanation :)
So... update... riding out today...EML comes on FFS... get it home quick as [email protected] not keen on pushing it several miles again. test the charge circuit while running at 5000 rpm as manual says.. 12.65v (was 11.75 not running). Pulled the stator plug and showing 0.48 across all terminals so that's not died (is was a new one) so guess the regulator needs replacing. I've pulled it and did test it prior to fitting the stator and it read correctly but perhaps has an intermittent fault of something. Can anyone recommend a replacement (with link?). There are some horrific aftermarket regulator experiences on Amazon reviews!!!!!

Cheers

RockingDad
oh damn :-\. I'm guessing the code from the EML was still the saem as before (i.e. charging problem)?

As far as I know there's only really the stator and the rectifier which make up the charging circuit so if it's not the stator then presumably it's gotta be the other. 13.6 or so would be more like normal running voltage I think. It might be worth cleaning up the contacts of the recitfier plug if they're crusty. That's a plug one could easily not push in properly but think you had..sorta thing.

Idk about getting an aftermarket one, I'd just get one off ebay like most bits. There must be decent used or pattern versions surely?

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