Thank you for letting me know. Ill have a look around that IC. Would ypu know the voltage IC should have? Thanks
Switch Lite had similar charging issues and BQ was at fault. New BQ installed, the board boots up fine except it thinks the battery is dying. I say it “thinks” because the batt voltage is the same. Batt 4.2v, plug in board reads 100% and starts to drop fast, unplug batt still 4.2v, plug batt in board accepts its a fully charged batt at 100% and starts to drop again. Tried several batteries and two known-good housings. Replaced 17050 twice. The board is drawing zero amps while off at USB port and at batt connector. BQ installed well. Don’t see any shorts and ohms to ground look fine compared to a working board I have.
If it isn’t a fuel gauge issue then possibly a shorted rail is causing the issue of fast battery drain or even possible an OL issue at the fuel gauge itselt.
I’d first measure resistance to ground on your SYS rail which is most easily found at the 2R2 inductor near BQ, Id then go ahead and at a minimum check resistance to ground on your primary rails (can be found on the inductos surrounding the main PMIC) as well as 3V3PDR (provided by the ENXX IC) if all is fine then perhaps a sub rail somehwere -
To verify you could measure current at the battery, not sure you’d get a current clamp around the battery wires though, so you could put your meter between the battery and board connecter to check draw or if your unable to do that you could remove the 2R2 inductor and just supply SYS voltage to the output end of the inductor pad and see what the current draw is. If you have a short you’ll see it here. If no, then points to the OL scenario mentioned earlier.
The fact the battery voltage still appears high though is suggesting the OL scenario though I’m afaid, I made a dedicated post somewhere detailing how to check this if you can find it. You can further verify this mind, if HOS is reporting 50% for example and you still measure say 4V then you know for sure it’s an OL situation
Knowing your favorite advice is to always check resistance to ground that is the first thing I did. I checked ohms and voltages compared to two working boards. Those seem fine. I spent some time checking your posts to make sure I didn’t ask something you posted about before but you got me again. Ill find it. Thanks.
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