Switch V1, 0.45A problem, No battery info

This switch won’t boot. Current draw ~0.4A

Hekate runs ok but freezes when trying to view battery info
RCM mode seems to charge battery normally (from 3.1V->3.9V in 1hr)
Emmc tested ok
Tested with good battery
No shorts found
Diode values around fuel gauge, BQ and M92 are okay
1V8, 3V3 lines ok, Sys line ok, ~13k ohms

Where do you think the problem is? Fuel gauge, BQ or something else?

Fuel gauge most likely at fault :+1:

Though looking at the reported temp might also be indacting the TMP IC is possibly at fault also (or the primary rail feeding it / or support circuitry)

Replaced the MAX17050 but no change :frowning:
Where can I find the TMP IC?



It’s worth noting here that it’s quite rare two have to seemingly different faults (presumably at the same time) in very different areas of the board - which in this case is preventing boot (both of these faults could both prevent boot) so it’s entirely possible there is a more serious underlying issue, for example the next link in the chain which has commonality with both these areas such as the SoC for example :frowning:

Can’t say I’ve ever encountered a faulty TMP IC before, though I have seen failure of the VIN line leading to it - IE: no continuity to the other areas of the board and in turn no voltage present at the TMP IC leg/s


I measured the T451 voltages and pin 8 (Serial Clock line, next to letter T) is ~60mV and should be 1.8V. The line goes under the SoC based on the board scans.

I see, probably indicating SoC related issue then :frowning: I would guess joint issues are more likely though in this case, so perhaps a reball would resolve… though Idely I’d probably transfer it over to another board just to rule out any potential board level issues.

It’s been a while since I had to deal with a TMP related fault and could well be wrong but is there no pullup resistor to 1V8PDR for this line? If there is then that could be the problem… though, as I say, regardless, with that secondary fault it’s more likely to be a more serious underlying issue.