E21 Error

[busybodiesfocus]

Have owned a Carrera Subway electric bike for 4 years.
It has been absolutely fantastic.

After charging the battery a few days ago I now get a "21" error when switching on.

I searched YouTube and a gentleman was recommending I check the torque converter, behind the crank.

Checked it over and its looks ok.

Removed the ECU and checked all wires and connectors. All looks OK.

I have just ordered a Crank remover bolt, I am going to remove that next and strip down.

Anyone else experienced this?

 

[saneagle]

Can't help without knowing what you have!!!

 

[busybodiesfocus]

Have owned a Carrera Subway electric bike for 4 years.
It has been absolutely fantastic.

 

[artspeck]

Error 21 fix video

 

[Nealh]

Is the carrera a TS PAS drive ?

 

[busybodiesfocus]

 

[saneagle]

View attachment 57497

You have a fault with your torque sensor, which is on the back of the chainwheel. It has a few common failures:
1. If the chain comes off, it can cut or break the wire, or even smash the whole sensor.
2. If you use the bike on winter roads or in dirty conditions, the stationary part jams to the moving part, and when you turn the pedals, it snaps one of the anti-rotation lugs off the sensor, then the sensor is pulled round every time you pedal until a wire breaks.
3. If you use the bike regularly in wet or dirty conditions, dirt can get inside, then the two optical sensors need to be cleaned after dismantling.

A simple inspection from the outside should reveal the cause of your problem, otherwise you need to pull the chainwheel off with a crank-puller and look more closely.

 

[Deleted member 16246]

You have a fault with your torque sensor, which is on the back of the chainwheel. It has a few common failures:
1. If the chain comes off, it can cut or break the wire, or even smash the whole sensor.
2. If you use the bike on winter roads or in dirty conditions, the stationary part jams to the moving part, and when you turn the pedals, it snaps one of the anti-rotation lugs off the sensor, then the sensor is pulled round every time you pedal until a wire breaks.
3. If you use the bike regularly in wet or dirty conditions, dirt can get inside, then the two optical sensors need to be cleaned after dismantling.

A simple inspection from the outside should reveal the cause of your problem, otherwise you need to pull the chainwheel off with a crank-puller and look more closely.

Your technical expertise in these matters must be a huge benefit to people who write in with problems. Great technical support and for free too.

 

[saneagle]

Your technical expertise in these matters must be a huge benefit to people who write in with problems. Great technical support and for free too.

All you have to do is look at one and use a bit of intelligence, imagination and judgement to get all the answers.

Some people are lucky to get the genes that enable them to do that and apply it to any situation. Other people get genes that make them good looking, others get genes that make them evil so they make a lot of money. The unlucky ones get genes that make them ugly, weak and thick, or believe things that aren't true, like most of what's written in the mainstream media.

Thanks for your nice comment. The only problem is that I need another cup of tea but I can get into the kitchen because my head will no longer pass through the door. Can someone send me a few insults to make it go back down?

 

[Deleted member 16246]

All you have to do is look at one and use a bit of intelligence, imagination and judgement to get all the answers.

Some people are lucky to get the genes that enable them to do that and apply it to any situation. Other people get genes that make them good looking, others get genes that make them evil so they make a lot of money. The unlucky ones get genes that make them ugly, weak and thick, or believe things that aren't true, like most of what's written in the mainstream media.

Thanks for your nice comment. The only problem is that I need another cup of tea but I can get into the kitchen because my head will no longer pass through the door. Can someone send me a few insults to make it go back down?

Ha ha ha ha .... We will never agree about some things, you and I, but I applaud your freely given help here. Well done on that.

 

[Deleted member 16246]

The unlucky ones get genes that make them ugly, weak and thick, or believe things that aren't true, like most of what's written in the mainstream media.

I'm not sure whether you think I got the genes that make people ugly weak and thick, or just the ones which make me believe things that are untrue.

 

[Saracen]

Can't help without knowing what you have!!!

He said

Have owned a Carrera Subway electric bike for 4 years.

 

[saneagle]

He said

Have owned a Carrera Subway electric bike for 4 years.

That's right, but he forgot to mention which version and whether it was a conversion or not.

 

[busybodiesfocus]

Have made more progress.
I have received my chain hub splitter and removed it.
Stripped it down and cleaned it, its all like new.

Removed the torque sensor completely.
It is like new. see pic.

If I turn the handlebar readout on with it removed, the error 21 has gone !

Does this sensor need replacing even though it looks OK ?

I see mine is a 4 pin, have seen them on ebay with 6 pins.

Thanks for your help

 

[saneagle]

Have made more progress.
I have received my chain hub splitter and removed it.
Stripped it down and cleaned it, its all like new.

Removed the torque sensor completely.
It is like new. see pic.

If I turn the handlebar readout on with it removed, the error 21 has gone !

Does this sensor need replacing even though it looks OK ?

I see mine is a 4 pin, have seen them on ebay with 6 pins.View attachment 57532

Thanks for your help

If you buy a replacement, you need one with 4 pins.

It looks like yours has had the cable pulled, so a wire might be broken in the cable. It's indicated by rhe zip tie pulled off, which is there to stop the cable getting pulled out. You might as well dig out the black stuff around the connector in the sensor, then test the continuity of each wire in the cable from one end to the other. It would me much cheaper to repair the cable than replace the sensor.

 

[Waspy]

Thanks for your nice comment. The only problem is that I need another cup of tea but I can get into the kitchen because my head will no longer pass through the door. Can someone send me a few insults to make it go back down?

Sure.

You're a baldy know-it-all skinflint with a Michael Jackson jacket who does zero maintenance on his own bike.

Happy to help.