The Koonlung K1S is a very nice dashcam, with GPS, emergency button and HD recording and everything is made quite small. The HD video has a bit of a low bit rate, but it’s still not bad.
That said, it became a piece of rubbish. No matter what kind of SD card is inserted, the software locks up and the whole device becomes useless.
I have tried all the versions of the firmware [⇓1]. I have tried to decompile the firmware [⇓2][⇓3]. Nothing worked, whatever I tried.
So the time has come to take the thing apart. It cannot be any more broken than it is now, so maybe it is a blown cap or something? It is not, by the first look. There seems to be a corroded button cell soldered onto the motherboard.
Alright. So what model is it? It’s not like you can just take it out and read what’s stamped onto it. Luckily I have a reference sheet in my archive that can be helpful. Hooray for being a data hoarder? >_>
The diameter is 4.8mm and the height is 2.0mm. The height is somewhat debatable as everything is small and kinda hard to reach. According to my datasheet, there are two candidates as a replacement battery:
- 4.8 x 2.15 – 1.55V – Maxell model: SR421SW – Seiko SB-A6 – Citizen 280-77 – GP 348
- 4.8 x 1.65 – 1.55V – Maxell model: SR416SW – Seiko SB-A5 – Citizen 280-75 – GP 337
As I want to get the exact battery, I grabbed a mini caliper and measured 1.65mm. There we go. It will be a SR416SW or anything compatible.
€5,46 has been paid for a set of 10 batteries because it was impossible to buy just one and now it is time to get the battery out.
More progress updates later!
[1] K1S-R158-50417-MPH – K1S-R179-50825 – K1S-R180-KPH – K1S-R180-MPH – K1S-R215-KPH
[2] k1s.bin_hlil – Type: Mapped, Platform: thumb2, Architecture: thumb2
[3] k1s.bin_hlil-arm7 – Type: Mapped, Platform: armv7, Architecture: armv7
