820-3332 no green light

[laptopcity]

820-3332 no green light, im a little confused , i have ppbus g3 and pp3v42, at u6900 pin 1 (sm_bc_acok) i have 3.4v pin 5 (adaptor_sense) i have 5.15v, at pin 4 (sys_onewire) i have 3.4V but no green light ?, forgot to say no signs of any liquid damage anyway

 

[JohnB8812]

Voltage on PPBUS? Tried known good DC in board? Trackpad, keyboard, and all the internals unplugged?

 

[dukefawks]

5V at adapter sense is a problem. Usually a bad magsafe board or crap under J6900.

 

[laptopcity]

ok thats wierd, the magsafe shows a green light on another board , but changed i anyway for a new one and guess what i have 2.9v at adaptor sense, but still no green light ,the other voltages are as before

 

[larossmann]

Please answer every question! Voltage at PPBUS_G3H?

 

[dukefawks]

Also these need to show an orange light after 2-3 seconds of green!

 

[laptopcity]

Hi , voltage at PPBUS_G3H is 11.96v , sorry what i meant about the dc in board was it seamed to work worked in another board

 

[JohnB8812]

Is that with just the board and MagSafe plugged in? Because if so that’s way too low. SMC suspect

 

[dukefawks]

11.96V is with battery connected....must measure without! And I ask again, does the light turn orange?

 

[laptopcity]

Hi, no the battery is not connected , the board is out of the laptop and i dont get any light at all. If 11.96V is low what should the voltage there

 

[JohnB8812]

If you don’t get a light...using known good MagSafe board? PP3v42 present? PPBUS should be 12.56 volts which makes the SMC suspect.

 

[laptopcity]

Hi thanks , yes dc in board ive tried 3 new ones , will try changing the smc, does the smc have to be from an 820-3332 or could i use one from a similar board ?

 

[JohnB8812]

The SMC may not be the problem answer the questions in this order.....

1. Is PP3v42 present?
2. If it is, what is the resistance between pins 17/18 and 27/28 of the ISL6259
3. What is your voltage on SMC_RESET_L?
4. Does the SMC area look like it has had liquid damage (obvious corrosion, red probe points)?

 

[laptopcity]

Hi
pp3v42 = 3.4v
resistance between 17/18 is 4.1 and 27/28 is 20.6
voltage on smc_rest_l = 3.34v
board looks completely clean all over

 

[dukefawks]

11.9V should be 12.56 or 12.3 at least. Is ACOK present? Did you check PPBUS on the fuse?

 

[laptopcity]

Hi yes ACOK is 3.2V at pin 14 u7000, dc in fuse is 20v , ppbus_g3h at fuse f7040 / f7041 has now changed to 5.3v which was 11.96v

 

[laptopcity]

Hi , yes ACOK is 3.2v at pin 14 u7000, dc in fuse f6905 is 20v and ppbus at f7040 / f7041 which was 11.9v has now dropped to 5.3v ?

 

[dukefawks]

ISL6259 could be bad. Also check the resistance between 17/18 and 27/28 again and also check voltage at DCIN pin.

 

[laptopcity]

looks like isl6259 went bad , now have green light , but now have 12.26V at ppbus f7040 / f7041, dc in fuse is still 20v, is 12.56v at ppbus now pointing to smc ??

 

[larossmann]

12.26v at PPBUS_G3H is too low. When the SMC communicates with the ISL6259 PPBUS_G3H will be 12.56v. Is SMC_RESET_L 3.4v?