How to: Replace Sena 10c battery

[noodles]

What: The Sena 10c is an integrated Bluetooth communication platform and video recording device. One of its primary shortcomings is battery life, which will decrease with age. Replacing the Sena 10c's internal battery, both to replace a worn battery that no longer holds a sufficient charge, and to increase the battery capacity from the original equipment.

 

This procedure should apply to other Sena models, with differences for the battery size but not voltage, and the exact details of getting it apart. The basic procedure is to disassemble the unit, cut the old battery off, solder in a new battery using the existing modular wiring, and put it all back together. I have to give some credit to this procedure for the Sena SMH10 as I used it as a guideline. I did contact Sena's support to verify voltage, size, and capacity of the original battery, too.

 

Why: Over time the Sena 10c will record for less and less time before depleting its battery. Since it cost maybe $300 and I use it every day for my commute, this was a pretty big priority to replace rather than buy a whole new unit.

Tools and supplies:

• 3.7v lithium ion battery 9.0mm x 40 mm x 30 mm (903040) or smaller (~$10)
  • The battery "code" is simply the dimensions where the first 2 digits are the thickness with decimal removed, and L x W in mm
  • The original battery is "903242", 3.7v, 1000mAh
  • The replacement I used was 903040, 3.7v, 1200mAh - a small increase in capacity
• Precision Torx drivers - very small Torx bit, maybe T7 ?
• Precision Philips head driver
• Plastic/nylon spudger
• Nitrile or vinyl gloves (recommended but not required)
• Tweezers
• Soldering iron
• Wire cutter/stripper
• Small heat shrink or electrical tape
• Double sided tape (recommended but not required)

Procedure

1. Ground yourself and remove your SD card before starting! Touch something metal and avoid sources of static electricity like carpets. Use vinyl or nitrile gloves to eliminate fingerprints damaging any components.
2. The Sena 10c comes apart in a clamshell fashion. Unfasten the Torx screws on the backside of the device. These are small delicate screws that should not require a lot of torque - don't strip the heads or you'll have a bad time. Once the screws are out, use the spudger to gently pry the device apart, starting in one section and slowly working the plastic apart going around the device. There is a water resistant gasket surface all around the clamshell's seam, don't bugger it! Only pry on the plastic surfaces, not the rubber! If you pry one area too far you might damage the finish or crack the shell. Be gentle and gradual with prying it apart. The jog dial fits into a splined metal shaft beneath it and will be the primary source of resistance but it is an interference fit only so it will come apart with gentle persuasion.
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   2. Red marks Phillips screws. Only 1 is visible while all the boards are attached, the other 2 are marked with arrows and are underneath the boards and attach a third board that has the jog dial and the battery's input plug.
   3. Yellow marks the modular connections between the 2 sandwiched circuit boards
   4. Blue marks the connection between the sandwiched boards and the board with he jog dial
   5. Purple marks the camera's delicate data ribbon
3. The battery is underneath all of the circuit boards attached to the plastic shell that it is all attached to. To get to it we will need to remove all the circuit boards and lift them out of the way. Remove the retaining screw, and use the spudger to pry apart the boards at the blue square's area where they attach to the jog dial's board. The boards are attached to the device via a red and blue soldered wire that supplies power to the camera, and via the camera's data ribbon. You don't necessarily have to remove the data cable and you can't remove the red and black wires, so peel the boards up and move them out of the way to gently rest on the table without stretching or kinking the cable and wire.
   1. The first circuit board you see is connected to another board beneath it like a sandwich using 2 delicate modular plugs. You can pry them apart with the spudger in an area that has no circuitry - I suggest near the USB port if you find this necessary. The camera attaches to the board by a delicate ribbon cable. Do not kink or bend this, be very gentle handling it! If you need to remove it to fit your battery (I did but you may not if yours fits better), flip up the retaining clip and then gently pull it away from the pins, not straight up!
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4. The battery lives in the gray square and is attached to the plastic via a piece of double stick tape. Use the spudger to gently pry the battery from the backing. Don't puncture it! Then use a small pick tool to ease out the modular plug (yellow box) a bit at a time until it hits the plastic shell, then undo the retaining screws (red boxes) for the jog dial board and remove it so you can unplug the battery.
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5. Cut the wires from the old battery leaving as much of the original wire on the plug's side as possible. Twist the wires together, and solder. If you need a soldering tutorial, check youtube.
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6. Now place the battery in the cavity where the original battery was, orienting where the wires lead to the modular plug. If you run them at the top where the camera button is, keep in mind that the blue squares show where that button will rest when everything is assembled, so don't park the wires too close to that area. Plug the newly soldered wires back into the jog dial board, refasten the board with 2 screws, and make sure the battery is in the little box cut out of the shell. Then carefully put the sandwiched boards back on top of the jog dial, and be sure the modular connectors for both the jog dial to the sandwiched boards, and the 2 sandwiched boards themselves, are all attached. That's 3 connections altogether. Then refasten the last retaining screw and reattach the ribbon cable if you had to remove it. Slide the ribbon back into the slot, don't try to press it! Then lock the ribbon in place again with the locking tab.
7. Power on the unit before you button it all back up and be sure the LED shines like it would if it was all reassembled. Turn it off before reassembling the front shell. If the shell won't lower properly, then you may have replaced the retaining screw(s) (2 on jog dial board, 1 on top of sandwiched boards marked in red) in one of the shell's holes instead of the internal hole.
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8. Once reassembled, charge the new battery to 100% before use. Keep an eye on the charging LED and put the unit in a fire resistant area if you're nervous. Dispose of the old battery responsibly!

Edited May 3, 2018 by noodles

[mjh937]

Thanks @noodles, nice write up.  I added a link in the Master List of How To's thread.  

[Mr.Puss]

@noodles ,  I havent had battery issues yet but this one will come in handy. Thanks!

[noodles]

@Mr.Puss I use mine through winter so the cold kills the battery w/ increased internal resistance - I think it might wear the battery more as well. I'm lucky if it can record for 45 minutes before turning off the camera for me. Now with my first ride to work after replacing the battery, the gauge was still full on my smartphone's display of the device's battery status.

[Kondox]

Hello man i loved ur tutoriel ,i would like to change my 10C's battery aswell ,from where did you order the battery please ?

[noodles]

On 5/3/2018 at 11:59 AM, noodles said:

Tools and supplies:

• 3.7v lithium ion battery 9.0mm x 40 mm x 30 mm (903040) or smaller (~$10)
  • The battery "code" is simply the dimensions where the first 2 digits are the thickness with decimal removed, and L x W in mm
  • The original battery is "903242", 3.7v, 1000mAh
  • The replacement I used was 903040, 3.7v, 1200mAh - a small increase in capacity

@Kondox follow the link in the post. Any 3.7v Li-ion battery should work, but that size I linked to fits for sure.

[unsatgoua]

Thanks for the install guide, just replaced my battery.  Charging now... wish me luck!!!

[JUBIO95]

Soo I ripped the camera ribbon like a noob... trying to find a new one that I can use is proving impossible with Sena10c in my search. Finding lots of Raspberry stuff but not sure if any of it is compatible. Can anyone help?

[noodles]

I would contact Sena support and tell them you need the ribbon - they might let you order it direct. Other than that I don't know what else to say. It's a specific fit and angle ribbon.

[Azdrewst21]

JUBIO95, I did the same thing. (Damaged the ribbon cable) Called Sena Support and they said they don't have access to spare parts. They are built overseas. I have looked high and low with no success. I may have to upgrade to 10C pro and use the old for a passenger helmet. (shrug)

Edited June 5, 2019 by Azdrewst21
run on

[noodles]

After a year of use the 'new' battery holds far less charge than the one it replaced. Seems it is lower quality. I find this again and again, I don't know where to find good quality replacement Li-ion batteries. Still, a low quality new Li-ion battery is better than none at all. I will be ordering a new one again and doing this procedure once more.

Wouldn't it be nice if Sena actually released that Sena 10c Evo model they teased?

EDIT: As of 08/2019 (1 year after the first battery change), I had to change the battery again. These AliExpress batteries are trash but they are all I can find. If anyone can find a higher-quality Li-ion battery please let us all know!

Edited August 31, 2019 by noodles

[noodles]

An Amazon seller has a battery for sale with the correct terminus:

https://www.amazon.com/Replacement-Motorcycle-Bluetooth-intercom-Compatible/dp/B07TY6WDDP/ref=sr_1_1?keywords=903040&qid=1569340878&s=gateway&sr=8-1

It's also grossly overpriced at $18, smh. Original battery part # is CP-SN10C

[sorkyah]

You want a battery with a higher "C rating" (charge/discharge)

Look around for an RC hobby shop near you, they will probably have a quadcopter battery that will work. get a battery that is similar size wise and you can probably find one that is a higher capacity