Help! Pendleton Somerby E (2019+) battery charger - shows charged (red light + green light) when not connected to battery


Finding my (electric) wheels
Mar 15, 2023
I have a 2019 Pendleton which I bought new from Cycle Rebublic.
Yesterday when I connected it to the battery, and plugged it in it showed one red ligth and one green light.
I know that the battery needed charging. as it ran out yesterday.
This morning, the lights ar the same, but the bettery is not charged.
When pressing the "show charge" button , no lights show up.

I do not have the know-how to open and test the charger.

Question - do I just but a new charger?
This site looks like a good choice: - £40 including shipping
MUCH cheaper than Halfords - £80 but I can get 15% discount, so £68


Esteemed Pedelecer
Nov 10, 2014
West Wales
Before spending your hard earned:
Is the bike still in guarentee?
If not, you need to test the output of the charger. For this you will need a digital volt meter, can be bought on tinternet for as little as a fiver. You are going to need one anyway to test polarity before buying a new charger,
e-bike batteries is a reliable source.


Esteemed Pedelecer
Aug 7, 2014
West Sx RH
Use a meter to test the charger voltage.
Plug the charger in the wall an turn it on, with the meter turn the dial to 200v dc .
Poke the Red probe in the middle of the charge connector and the Black to the metal outer sleeve, you will then get a voltage reading . It should read 42v, if so your charger is ok and the fault lies with the battery .
Whilst at it check the battery voltage at the discharge point of the battery, place Red probe on + and Black on - to get the battery voltage.


Esteemed Pedelecer
Oct 10, 2010
You need to check the voltage on both the charger and the charger socket on the battery. if the socket has no voltage, a fuse has probably blown. If the charger has no voltage, it's a bit more complicate. Cross that bridge when we come to it. When you check the charge socket, you have to be very careful not to shorth the probes or pins. It's best to use a spare jack that has no wires on it or cut a jack off an old charger of some sort so that you can put your probes on the separated wires. You can probe the socket directly if you have a steady hand and good eyes. There's a blade at the side and a pin in the middle, which you attach the probes to, but the pin is quite close to the blade.


Finding my (electric) wheels
Mar 15, 2023
I bought a digital volt meter.
But before I started fiddling about, I pressed the lights on the battery, and... they all lit up ... Whack The Frog!!!
I put the battery back in the holder and it powered the bike.
When the battery went down, I charged it up again, and all is OK!
I didn't even get the volt meter out of the box.
If I read this (rather than wrote this) I'd say "User error", but I know what I saw, and I am at a loss *?*
Oh well, it works, and that is the main thing.
Thanks all for your help and suggestions; it it goes wrogn again, I've some steps to pursue.


Esteemed Pedelecer
Jan 26, 2018
Both the older and newer versions of the instruction manuals (attached below) state
"If the battery is not used for 24 hours or longer, it will automatically go into sleep mode. Press the power button on the battery for three seconds"
This might explain although I have never seen it happen with my daughters 2017 pendleton.

PS. There is a further comment in the newer first manual that states
" When the battery voltage is enough low (33.5V for 36V pack/23.5V for 24V pack) and rest more than 24 hrs, the BMS will shut down automatically to save power. To wake up BMS, you need to insert charger into battery pack.


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