Problem with my Bafang HD

[Hixyhicks]

I'm sorry,I'm not sure what I'm doing i have added 2 pics . Positive and minus .

I have measured the 2 other cables and im getting the same readings ish

 

[vfr400]

That's correct. 8.81K is about right. What about the other five readings?

Sometimes, one set of readings will continuously climb, in which case just take a snapshot of the reading when you connect. It's because a capacitor is charging. You can reset it by shorting out the red and black wires, which discharges it. Alternatively, try swapping your probes the other way round. You're measuring resistance, so it doesn't matter which way round they are, but one way charges the capacitor.

 

[Hixyhicks]

These are the other readings .Thank you for your help .If the mosfets are not good i can order them and do the work at work .

 

[vfr400]

These are the other readings .Thank you for your help .If the mosfets are not good i can order them and do the work at work .

You're making it really difficult. I see red to green twice, red to blue and black to blue. We already had red to yellow twice.

Please make it simple - just 6 numbers. Copy and paste below into your next post and replace the ??? with the values.
Red to blue: ???
Red to green: ???
Red to yellow: ???

Black to blue: ???
Black to green: ???
Black to yellow: ???

 

[Fordulike]

Just buy a new controller. It'll solve any uncertainty that the issue is the controller. If it turns out to be a problem other than the controller, at least you'll have a spare one for the future.

BTW, changing out MOSFETs on these are a PITA

 

[Hixyhicks]

Red to blue: 8.83
Red to green: 8.84
Red to yellow: 8.87

Black to blue: 8.88
Black to green: 9.51
Black to yellow:9.67

Sorry i learn by being shown .

I dont wont to buy another controller because the price has gone mental and also i like to repair stuff .£30 for some mosfets is alot better than £100 or more for a new controller .The controller maybe fine .I dont know .

 

[Fordulike]

I dont wont to buy another controller because the price has gone mental and also i like to repair stuff .£30 for some mosfets is alot better than £100 or more for a new controller .

Yeah, it's not a cheap hobby.... just don't tell the wife

 

[Hixyhicks]

From the video's ive watched i believe my controller is good .So god knows whats wrong .I may replace the rear derailleur and hanger and see if its that .

 

[Fordulike]

If you suspect it might be the bike's drivetrain and possibly not the actual motor/controller, try taking the chain off the chainring and rotating the pedals. Bike must be powered up.

You'll get an error on the display IIRC, coz the rear wheel sensor won't detect the wheel turning, but it'll run long enough to see if the problem is still there.

 

[vfr400]

Red to blue: 8.83
Red to green: 8.84
Red to yellow: 8.87

Black to blue: 8.88
Black to green: 9.51
Black to yellow:9.67

Sorry i learn by being shown .

I dont wont to buy another controller because the price has gone mental and also i like to repair stuff .£30 for some mosfets is alot better than £100 or more for a new controller .The controller maybe fine .I dont know .

The results are fine - exactly where they should be.

There's reason to replace the derailleur. If you think there's something wrong with it or the cassette or the free-hub, ride the bike for a bit with the motor switched off. If all is well like that, then it's not where the problem is.

in any case, derailleurs can't really give problems like that unless you don't have it set up properly, which would be an adjustment, not replacement. An improperly adjusted derailleur would cause the chain yto jump. Another cause of chain jumping is some debris caught in the cassette, like a little stone, a bit of a stick or something like that, but you'd only get jumping in one or two gears.

Worn pawls or rust in the freehub can also cause jumping of the drive. that would show up if you ride the bike without the motor switched on.

 

[Hixyhicks]

Thank you ,i will have a look when i get time .

 

[Hixyhicks]

Ive seen ebike testers on Amazon can you recommend one for me .One that works with bafang connections. Also where is the best place to buy a new controller .Most of UK stockist are either out of stock or expensive .My bike is still miss behaving .

Cheers

 

[vfr400]

Ive seen ebike testers on Amazon can you recommend one for me .One that works with bafang connections. Also where is the best place to buy a new controller .Most of UK stockist are either out of stock or expensive .My bike is still miss behaving .

Cheers

There isn't one. They're designed to work with hub-motors and old controllers. They can be adapted to work with other things, but you'd need to change all the connectors. All they do is test that you have no shorts on the motor coils, the throttle has power,the hall sensors works and that the controller tries to power the motor.

 

[Hixyhicks]

Firstly thank you for all the replies ,as was said in this thread check the simple things first .Which i didnt .The problem in the end was the rear cassette.I replaced it and now all is working as it should .