Bluetooth Speakers Turn Off Within 10 Minutes
Received Bluetooth speaker with fault symptom speaker automatically turn off within 10 minutes
On arrival of the speaker I turned ON the Power and started playing some songs from my mobile phone. It played for 5 minute & speaker automatically turned power OFF. So for further inspection I have to open the speaker unit.
I tried to pulled up the front grill gently using needle tool. But some time front grill is fitted using glue you can see border of grill is having the glue.
It took more time for opening the grill because of glue. While removing grill misshaped because it is made of thin aluminum sheet.
Removed all the screws from the top.
for this types fault suspected area is
1) On/ off switch.
2) Battery section.
3) Main circuit board it self.
Removed the circuit for physical inspection.
Checked On /Off switch using Multimeter seems OK.
Checked Battery Charging connector that is also OK…… Removed all connectors & re fitted again for testing still same problem. Checked voltage on Battery it shows 3.83 within normal operating range (4.2v to 3V)
So now seems culprit is main circuit board……… but before fault finding on the circuit board I decided to check with another working battery. Because sometime Battery showing voltage in working range but it won’t hold enough current for a long time because of the bad battery.
Took one working Battery for testing form my battery BOX. I have salvaged few from some old laptop non-working batteries.
Now I took out the Battery & tested the speakers it works for half an hour. It indicates the original battery in the speaker is bad.
So for curiosity I re checked Voltages on old battery.
You can see BMS Output voltage is only 0.9v & Speakers need at least 3V for operate. So here problem is with BMS Circuit……. Still I decided to use working battery which is fully charged. So I took one fully charged battery as a replacement. Took apart old battery for using Cables with connector on replacement battery.
Removed top sleeve cover (Blue) & found one more circuit on Battery which is called BMS. (Battery Management System).
Removed BMS circuit to test with working battery ……But still same low out put on the working battery also.
Hence decided to use battery without BMS circuit because the charging IC T4056 itself take care of charging.
re assembled the unit & tested it works nonstop for 4 Hours……
Speaker is now ready for the pickup by the customer.
This article was prepared for you by Yogesh Panchal who works as a Computer Hardware Engineer in Mumbai India.
P.S- Do you know of any your friends who would benefit from this content that you are reading now? If so, forward this website to your friends or you can invite your friends to subscribe to my newsletter for free in this Link.
Note: You can check his previous repair articles on ONEPLUS Bullets Wireless Z Bass Bluetooth Not Working No Power
(63)Dislikes
(0)
22 Comments
Leave a Reply
Mark
February 4, 2023 at 3:38 pm
Well done Yogesh,
It is easy to get caught out if components are not tested under load.
Good catch!
Yogesh Panchal
February 5, 2023 at 4:14 pm
Thanks you! Mark
Albert van Bemmelen
February 4, 2023 at 4:36 pm
I understand that the bms board normally also protects the battery from wrong overvoltage and checks its temperature. So I do hope it is still safe to use the 18650 cell with its at maximum charged 4.2V voltage without that board?
Tayo
February 5, 2023 at 12:12 am
Very true Albert. While the chances of something bad happening is relatively slim (so many devices use these 18650 without a BMS) I would be cautious about it. What I did once was replace the battery pack with a female
DC plug and used an external power supply to supply the needed power. This made it less "portable" but made it much safer and reliable.
Yogesh Panchal
February 5, 2023 at 4:34 pm
Tayo,
Battery is just for mobility use or for Home use External power is the best solution.if your device is using Charging Protection IC I.e.TP4056 on the circuit it will take care of charging precautions Measure.
Yogesh Panchal
February 5, 2023 at 4:30 pm
Albert,
IC TP4056 is having all the protection for battery charging & specially designed for charging single cell 3.7V 1 Ah or higher lithium-ion (Li-Ion) cells such as 16550s & 18650 that don’t have their own protection circuit.
this IC is having protection like i.e. Over voltage /Current monitoring
Please find Datasheet in this link.
https://dlnmh9ip6v2uc.cloudfront.net/datasheets/Prototyping/TP4056.pdf
Parasuraman S
February 4, 2023 at 5:45 pm
Vow! That was a professional fix knowing how the circuit works very well! Well done and many thanks for the wonderful tips too!
Yogesh Panchal
February 5, 2023 at 4:35 pm
Thank you! Sir.
Yhoni
February 4, 2023 at 8:26 pm
Thank you for to share it.
Yogesh Panchal
February 5, 2023 at 4:36 pm
Yhoni, You're Welcome!
Tayo
February 5, 2023 at 12:14 am
Well done Yogesh.
I had a robot vacuum that had a similar issue with the BMS.
Very simple circuit but I couldn't figure out what was wrong with it without the aid of magnification (which I didn't have access to a the time.
Yogesh Panchal
February 5, 2023 at 4:46 pm
Thank you! Tayo,
Very difficult to repair BMS circuit because of unavailability of spares.
Imoudu.O
February 5, 2023 at 3:55 am
Well done Mr Yogest, With the removal of bms it's most likely the life span of battery is going to be shortened, Bluetooth will continue working though.
Thanks for sharing.
Yogesh Panchal
February 5, 2023 at 4:53 pm
Imoudu.O,
You can't predict behavior of Battery life span using BMS because here both went bad.
Henrique J. G. Ulbrich
February 5, 2023 at 4:19 am
Good job, Yogesh. Thanks for sharing. According to your description, the BMS is damaged, at such a point that is shorting the battery. I agree with the IC T4056 charges the battery, but only this. The general protection of the battery is performed by the BMS. Taking it out, the battery goes thoroughly unprotected.
Yogesh Panchal
February 5, 2023 at 5:04 pm
Henrique J. G. Ulbrich,
IC T4056 module is specially designed for charging single cell Module without BMS.
it has Current monitoring function for battery in built.
I have already shared datasheet of IC in reply to"Albert".
Thanks! for your comment.
Tito Kanshulu
February 5, 2023 at 1:04 pm
Job well done Yogesh. Thanks for sharing
Yogesh Panchal
February 5, 2023 at 5:05 pm
Tito Kanshulu,
You're welcome.
Waleed Rishmawi
February 6, 2023 at 4:44 pm
great work my friend and thanks for sharing. have a blessed day
LLOYD BOND
February 8, 2023 at 2:01 am
GOOD DIANOSTICA
Yogesh Panchal
February 15, 2023 at 4:00 pm
LLOYD BOND,
Thanks!
Yogesh Panchal
February 8, 2023 at 6:19 pm
Thank you! Waleed