820-2915, slow battery charging

yobad

Member
820-2914-B, it has some issue with charging,
when I plug the MagSafe it charges the battery consuming 2.9A directly after it decreases the amper consumption to 1.2A
I think it has an issue with the Amperomter sensor after it charges the battery slowly.

u7000 replaced
battery SDA/SCL 0.530 diode mode/ 3.4V


who to start this troubleshooting?
 

PJs

New member
I'm not an expert, but from my experience this is usually caused by a bad aftermarket battery. Change U7000 and Q7055 at once and never connect that bad battery again.
 

yobad

Member
Sorry for being late on this..
it is 2915
Resistance between pin 19/20 9.2omh
27/28 26ohm

I didn't replace u7000, it is a new board but it has the same issue.
 

2informaticos

Administrator
Staff member
When battery voltage increases, charging current decreases, this is normal behaviour.
Can you fully charge the battery?
 

yobad

Member
the battery voltage 10.8v
it shows on the system 8%

I put this battery on other known good board it charges with 2.5amp.
 

2informaticos

Administrator
Staff member
For such low level yes, should charge with high current.
I was thinking you had battery almost full...

Check SMC_DCIN/BMON_ISENSE levels.
 

2informaticos

Administrator
Staff member
"BMON_ISENSE 3v"
There is your problem!

Post CHGR_BMON level and check resistance between pins 17/18 of ISL6259.
 

yobad

Member
Yes I found a broken trace on the R5422 and I repaired it
Q7055 replaced also but I didn't found a short in it
thanks for help
 
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