Hi all.
The U7000 (ISL6259AHRTZ) on my K90i is getting very hot in a short
time after plugging in the power connector. This started after having
accidentally shorted C7050.
The cap seems fine (desoldered, measured no short).
Is it possible that some other component is broken or do I have to
replace U7000?
I read somewhere in this thread that U7000 has its own power supply
depending on CHGR_DCIN (measured 16.5V) and the battery (didn't
measure that one). However, there's only 0.5V on R7001.
U7000 => broken?
Thanks
The ISL6259 generates its own 5V power and that is what you should see on R7001. If you have 0.5V then it sounds like the ISL6259 (U7000) has failed.
I have replaced lots of these 6258 and 6259's. I buy them 10 at a time
🙂 They seem to be a common failure point.
The ISL6259 was indeed defective. I replaced it and the power bus
was back at 12V on battery.
However, G3H was still missing (0.4V instead of 3.42V). The reason for
this was a defective D6990 (only one of the two diodes was burned up,
which is why I didn't suspect it earlier).
If somebody has a similar problem and, like me, no SOT-323 general
purpose diode package: it *is* possible to use two SMD diodes. Simply
solder the second diode to the probe pin instead of the original
output pin
🙂
Just for people experiencing the same: I measured a voltage of ~0.45V
for G3Hot and measuring the voltage behind D6990 gave me ~1.2V
so I initially assumed that the circuitry behind D9660 is broken.
This was not the case as the voltage *before* D9660 was 16V as it
is supposed to. This lead me to the conclusion that D9660 must be
broken even when the battery diode in D9660 was working.
The 1.2V I measured was just leakage from some other part of the
circuitry.
