820-00165 PPBUS_G3H missing

[Bouba148]

No History bought on ebay as dead board, looks clean no Liquid Damage

PBUS_G3H: 0.01V
Resistance to gnd: 3.2MOhms

at U7100
R27-28: 20.3 Ohms
R17-18: 3.2 Ohms
CHGR_AGATE: 14.00V it should be much less to be able to close Q7180 no?
CHGR_DCIN: 15.10V

So Am I right to suspect U7100? maybe anything else like Q7180?

 

[2informaticos]

We need more voltages for U7100; 3, 9, 12, 13, 14, 15, 19, 20.
Do you get correct 3V42 and magsafe light?

 

[Bouba148]

Hi 2Informaticos,

I've just replaced the U7100 and now I have the green light before it wasn't the case.

Now:
ppbus_g3h: 8.20
PP3V42_G3H: 3.421V
PPVRTC_G3H: 3.421V

No S5 state:
PP5V_S5: 0 V
PP5V_S4RS3: 0.082V
PP3V3_S5: 0.232V
PP3V3_SUS: 0.372V
PP3V3_S4: 0.05V

I've read in the forum that when ppbus_g3h is around 8.20V it means that U7100 is not talking to the SMC, is that right?

 

[Bouba148]

PM_SLP_S5_L: 0V
SMC_ADAPTER_EN: 0V
PM_BATLOW_L: 0.233V
PM_PCH_PWROK: 0V
PM_DSW_PWRGD: 0V

at U1950:
CPUVR_PGOOD_R: 0.495V
SYS_PWROK_R: 0V

at U1900:
32Khz OK

Y5110: 12Mhz OK

Dead SMC?

 

[Bouba148]

I have signal on SMBUS_SMC_5_G3_SCL and SMBUS_SMC_5_G3_SDA
meaning there is dialogue between SMC and U7100.........no?

 

[2informaticos]

Check resistance to ground on SCL/SDA lines of battery bus.
Also check their voltages.
You must get less than 1% difference...

Check if R7100 is OK and assure good solders at U7100.

 

[Bouba148]

Resistance to ground for SMBUS_SMC_5_G3_SCL and SMBUS_SMC_5_G3_SDA: 388.2KOhms Both
Their voltages are around 3.44V as it's "talking" so it's like burst mode at the scope.
I've also reworked all the U7100 pins one by one in case of bad soldering

U7100:
1: CHGR_AGATE 0V
2: CHGR_DCIN 14V
3: CHGR_ACIN 3.80V
4: CHGR_VFRQ 3.319V
5: CHGR_ICOMP 1.115V
6: CHGR_CELL 0V
7: CHGR_VCOMP 0.797V
8: CHGR_VNEG 1.369V
9: CHGR_AMON 0.031V
10: SMBUS_SMC_5_G3_SDA 3.44V
11: SMBUS_SMC_5_G3_SCL 3.44V
12: PP3V42_G3H 3.42V
13: CHGR_RST_L 3.390V
14: SMC_BC_ACOK 3.391V
15: CHGR_BMON 0.064V
16: CHGR_BGATE 8.07V
17: CHGR_CSO_N 8.20V
18: CHGR_CSO_P 8.20V
19: PP5V1_CHGR_VDD 5.060V
20: PP5V1_CHGR_VDDP 5.022V
21: CHGR_LGATE 0.604V
22: GND
23: CHGR_PHASE 8.20V
24: CHGR_UGATE 8.47V
25: CHGR_BOOT 12.53V
26: CHGR_SGATE 13.71V
27: CHGR_CSI_N 13.93V
28: CHGR_CSI_P 13.93V

 

[2informaticos]

PPBUS_G3H, 8.2V without anything connected to the board?
Disconnect anything, including LIO flex; keep only 5 pins power cable (no battery).

Did you try other ISL6259?
If still the same, should be SMC issue; you can try reball it first.

 

[Bouba148]

I've disconnected the LIO board, I've just let the power cable and still PPBUS_G3H is 8.20V the board is pulling 0.018A when I use the DC power supply.
Let me try another ILS6259.

 

[Bouba148]

tried with another ISL6259 it's the same : No S5 and around U7100 it's more or less the same voltages PPBUS_G3H is 8.19v

I think that tomorrow I will pass it in the UltraSonic Cleaner bath just in case there's crap under the SMC.

 

[Bouba148]

Smc_clk32k: 0v
pch_susack_l: 0.365v
pm_pwrbtn_l: 0.233v

 

[2informaticos]

You miss many other previous signals...
Reball SMC first.

 

[Bouba148]

Replaced SMC:
PP5V_S5: 5.032V
PP3V3_S5: 3.343V
PP3V3_SUS: 3.340V
PPVRTC_G3H: 3.345V

When I turn the power ON, I can hear a little "tic" on the board it come of the CPU area of the board not from the fan but only when the LIO flex cable is connected.

I can now have access to the U6100 with the Medusa.
When I try to force the SMC bypass mode I just have 1 quarter fan spin and PP5V_S4RS3 pulse once.

 

[2informaticos]

ALL_SYS_PWRGD pulses?
If yes, check for pulse at pins 7 & 3 of U1950 too.
Use R5115/16 pads to trigger SMC_ONOFF_L.

 

[Bouba148]

ALL_SYS_PWRGD is pulsing once
at U1950:
pin 7 is pulsing but not pin 3 because SMC_DELAYED_PWRGD is missing
Also each time I trigger the SMC I hear that little "tic" noise.

Maybe bad soldering job for the SMC or BAD/ not compatible SMC ( not sure if it's coming from the same exact board) but it has the exact same reference but who knows what Apple has programmed into it.
to be 100% sure I have to reball the original one, but I don't have 0.3mm balls and the soldering past I have is very bad that's why I took the risk to test with that other "new" SMC bought on Aliexpress......

 

[2informaticos]

Ooops, no way to work with new SMC.

Don't bother with the marking code, just pull out an SMC from the same board.

For reballing SMC, is best to use 0.35mm balls, even 0.4mm is OK.
Don't waste time with solder paste, is a pain.

 

[Bouba148]

Got it. Thanks for your precious advices

 

[Bouba148]

I've reballed the original SMC and resoldered it :
I'm back at the exact same point like at the begning: No S5 state
Which means ( I think ) the SMC is bad and have to be replaced by one from the same exact motherboard.