Jump to content
Joe Engineer

ANSWERED Sondors Fat (Custom) loses power

Recommended Posts

I've had my Custom since last year and have noticed this problem in the past couple days.

While riding I notice the LCD display goes blank. The Sondors 3 LED indicator goes out. After around 30 seconds the LED indicators come back on and I can turn the LCD display back on. It comes on set to PAS 1 no matter what level I was using before this happens.

The battery has a good charge  I can be going up a hill or just tooling around slowly when this occurs. Weather here is in the 90 degree range today.  I wonder if this is a temperature issue, though last year I didn't have any problems.  Could it be a battery going bad? There are those lights and button on the battery, I was never sure how to use them.

 

Share this post


Link to post
Share on other sites

OK, after the heat wave was over I felt like looking at the bike wiring and battery.  With the battery removed from the bike I charged the battery for a couple hours and the charger light was green.  I turned the battery ON and pressed the test button- all LEDs were green except the one at the 11 O'clock position was red. With a voltmeter, I measure 40 VDC at the battery terminals with the switch ON and 33 VDC with the switch OFF.  If I press the test button, the 33 V drops to zero while I hold the button in. While that may be meaningless, it's something to compare with a known good battery if I had one.  I'll have to try to set it up so I can monitor the voltage while I run the motor.

I just have a feeling that I'll need a new battery and if I have to go to that expense I may as well upgrade to a 48 or 52 Volt and a new controller.

 

 

Share this post


Link to post
Share on other sites

I have a extended range battery from an original that I removed the first  week when I changed to a bigger battery.

Share this post


Link to post
Share on other sites
2 hours ago, roknroe said:

I have a extended range battery from an original that I removed the first  week when I changed to a bigger battery.

Is that the 12.8 AH one and is it working?

Want to sell it? If it's a reasonable price I might grab it.

EDIT: I looked in the Marketplace and see it is listed.

Edited by Joe Engineer
add more info

Share this post


Link to post
Share on other sites

I've been doing a little research to see if it's possible to take these batteries apart and replace the bad cells. There are YouTube videos showing what's inside and it shouldn't be a huge deal if you can get the same type of replacement cells.  I might go ahead and take my bad battery apart after I get the replacement on my bike.

 

Share this post


Link to post
Share on other sites

Well, I bought a spare battery and a few other parts.To make a long story short, I still had the power drop out problem. I even swapped out the controller to no avail. I noticed I could make the power cut out by applying pressure to the battery as it sits in the cradle. Turns out one of the battery contact pins in the battery cradle was not fully extended. It's stuck about half way down. I have a spare cradle which I'm going to swap out tomorrow. Not sure how easy the stuck pin might be to repair but I'll give it a try.

Share this post


Link to post
Share on other sites

Member Josh found loose cradle terminals in the cradle base on his Fat.

Poor Battery to Cradle connections can lead to arching and high current drain and can melt the plastic around the cradle pins.

image.jpeg.460181aebee7ca43d0f0c2b7c7188c24.jpeg

      Reddy

  • Like 1

Share this post


Link to post
Share on other sites

Post Mortem on my battery cradle- Both of the nuts on the terminals were loose enough for me to turn the wire around. The Negative terminal  had  heated up enough to deform the plastic in the base and locked the spring loaded terminal in the depressed state. Interesting that it took a year for it to show up.

I checked the connections on the replacement cradle and they needed some tightening. Bad quality control, if they even have it where these are manufactured.

I think things are back in order on the bike, will rake it out tomorrow.

Share this post


Link to post
Share on other sites

Unfortunately this is a not-uncommon problem.  Over time some terminals work loose.  Typically the terminal that is stuck is beyond repair.  Yours sounds like it was in the early stages as you didn't report any arc'ing, serious melting and you didn't let any smoke out.

You got out easier than most in that you had spare parts in hand and you knew how to swap things around.   Usually someone has to wait for another cradle to arrive.

For future reference here is one replacement cradle
https://lunacycle.com/cradle/

Be careful when you buy from other vendors as these bottle batteries are sold in many different lengths and the cradle you find somewhere else may not fit a Sondors.

p.s. in some cases the cause has been traced to the operator not properly seating the battery.  Make sure yours is locked in and seated properly before you ride.

Share this post


Link to post
Share on other sites
Guest
This topic is now closed to further replies.



×

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use and Privacy Policy.