Released on September 19, 2014, this 4.7" screen iPhone is the smaller version of the iPhone 6 Plus.

3058 Questions View all

No power no detect on itunes from a good batt

HI guys,

I have an iPhone 6 in for repair and its got me a little stuck.

iHave a known good working battery hooked up and no detection by itunes or CPU isnt getting warm.

Took the following voltages thus far VCC_main from CF 5202 ( 1.1v) these are all taken with direct power from mains via charging dock.

Values from around tristar

C1299 on PP3v3 reads (1.33v)

C1704 on tristar PIN ( 3.36v)

C1738 on tristar by pass ( 1.90v)

C1700 PP3V0 (1.420)

SOme values from BATT VCC

C1695 (1.1v)

Any help in right direction will be much appreciated.

Kind Regards

Nathan

Answered! View the answer I have this problem too

Is this a good question?

Score 0

Comments:

Changed tristar. Still nothing, no heat being generated at all through the board.

by

PP5V0 - is down at 3-4.2v which is a little low at C1408

by

Add a comment

2 Answers

Chosen Solution

Some of those test points are not really important. Focus on the main power rails first (PP_BATT_VCC, PP_VCC_MAIN and PP5V0_USB). Seeing as how those rails are not where they should be, that's what you must troubleshoot first.

Either your PMIC is bad (hence all of the low voltage readings) or something is dragging it down (it would be hot though). So check all your main power rails (see above) and then check all of the rails generated by the PMIC. Note which ones are there vs which ones are low vs which ones are possibly shorted and then take your troubleshooting forward.

Get back to us with your findings.

Was this answer helpful?

Score 3

Comments:

Hi mate,

Thanks for response.

I have the following readings

vcc main - 2.3/2.4v

vcc batt - 2.4v

pp5v0 - 3.4- 4.4v flucuates

PP3v3-acc ( not sure if this matters ) - 0V

Mains power & dock connected

PS. If I say something stupid bare with me im still learning haha. But I have a fair idea of what im doing

t

by

Going off lines from scematic now -

PP gpu/1.1v - 0V

by

pp tristar pin - 4.3/4v

by

PMC is what I would've suggested next. Thanks @refectio. Never done one of those. And aren't there ...3? Pretty sure there's definately 2. And you'll want to test those circuits as well

by

Yep

Apple/Dialog 338S1251-AZ Power Management IC

Qualcomm PM8019 Power Management IC

Also, unrelated, when someone has trouble hearing, and you try replacing the front camera flex, and that doesn't take. Then it's either the socket, or the Cirrus Logic 338S1201 Audio Codec?

by

Add a comment

If you test a known good battery and lightning dock. I'd go with the tristar

Was this answer helpful?

Score 2
Add a comment

Add your answer

Nathan Pelling will be eternally grateful.
View Statistics:

Past 24 Hours: 0

Past 7 Days: 3

Past 30 Days: 16

All Time: 73