(347) 552-2258 [email protected]

820-00165 / Green & Orange Light / No Power / Low PP5V_S4RS3

S

SairFecht

Member
Apologies if this turns out to be something really stupid, I'm operating on not a lot of sleep here.

I've got a 820-00165 that came in, no power. The board is immaculate, I've been over it several times and no signs of any corrosion at all, anywhere.

Some readings:
PPBUS_G3H - 8.58
PPBUS_S5_HS_* - 8.58
PPDCIN_G3H_ISOL - 18.19
PPDCIN_G3H - 18.19
PP3V42_G3H - 3.42
PPVRTC_G3H - 3.33
PP5V_S5 - 5.02
PP5V_S4RS3 - 1.159
PP5V_S0 - 0.00
PP3V3_S5 - 3.33
PP3V3_S4 - 0.00
PP3V3_SUS - 3.33
PP3V3_S3 - 3.33
PP3V3_S0 - 3.33
PP3V3_S4SW_SNS - 0.04

PP5V_S4RS3 is the obvious one out here, but I can't find anything wrong on any components connected. Nothing that jumps out to me as a short to ground anywhere.

Anyone able to give me a nudge in the right direction? Thank you!
 
2informaticos

2informaticos

Administrator
Staff member
Post diode mode to ground on L7520; red probe at ground.
Also post voltage for pin 4 of U7501.
Be sure C7524 and R7545 are both good.

Do you get PM_SLP_S4_L high level?
 
2informaticos

2informaticos

Administrator
Staff member
PM_SLP_S5_L also missing?
Check if reacts when you trigger SMC_ONOFF_L signal; use R5115/16 pads for this.
Are you using original Magsafe 2 (two) charger?
PM_BATLOW_L will stay low, if not.
 
S

SairFecht

Member
Replaced R7545 and C7524 to no affect (though certainly R7545 did need replacing.

2informaticos said:
PM_SLP_S5_L also missing?
Click to expand...

Yes, 0.03v

2informaticos said:
Check if reacts when you trigger SMC_ONOFF_L signal; use R5115/16 pads for this.
Click to expand...

Doesn't appear to. I notice a tiny fluctuation in the power supply draw, 0.79 becomes 0.80 and then drops again.

2informaticos said:
Are you using original Magsafe 2 (two) charger?
Click to expand...

Original genuine MagSafe 2 cable on a DC power supply. No discernible difference using a full genuine MagSafe 2 charger.

2informaticos said:
PM_BATLOW_L will stay low, if not.
Click to expand...

Can confirm 0.00v with DC supply, 3.33 with Genuine charger, other readings appear unaffected.
 
Last edited:
2informaticos

2informaticos

Administrator
Staff member
Board will NOT start with low level at PM_BATLOW_L.
Why do you insist with desk power supply???

Post PM_RSMRST_L and PM_PWRBTN_L levels.
Check for any reaction (drop pulse) at PM_PWRBTN_L when trigger SMC_ONOFF_L.
BTW, do you get 3V at SMC_ONOFF_L?

Check if start in SMC bypass.
 
S

SairFecht

Member
2informaticos said:
Board will NOT start with low level at PM_BATLOW_L.
Why do you insist with desk power supply???
Click to expand...

- It's a genuine cable, which I thought was what was important
- It's not been an issue before
- At least two other 820-00165 boards this week alone and they've worked fine with this setup
- I don't want shitty boards killing ?79 genuine chargers

But now that I know there's the potential for problems, I'll keep an eye out. Every day is a school day.

2informaticos said:
Post PM_RSMRST_L and PM_PWRBTN_L levels.
Click to expand...

3.33v & 3.41v


2informaticos said:
Check for any reaction (drop pulse) at PM_PWRBTN_L when trigger SMC_ONOFF_L.
Click to expand...

Yes, drops when triggered. I missed the exact value, but looks to be about a 1v drop.


2informaticos said:
BTW, do you get 3V at SMC_ONOFF_L?
Click to expand...

3.41

2informaticos said:
Check if start in SMC bypass.
Click to expand...

Unfortunately not.
 
S

SairFecht

Member
Re-tested PM_BATLOW_L from a different point with the DC supply and it's fine, it's at 3.3v. I was testing on Q3000 and I think the contact point was too fine for a reliable multimeter probe connection. Apologies.
 
2informaticos

2informaticos

Administrator
Staff member
"Yes, drops when triggered."
Are you sure no pulse at all at any PM_SLP_Sx_L signals???
That points to bad PCH, or some if its signals is not good.

Check all 4 (four) RTC signals (page 12).
Also check PCH_DSWVRMEN and PM_DSW_PWRGD.
 
Last edited:
S

SairFecht

Member
2informaticos said:
"Yes, drops when triggered."
Are you sure no pulse at all at any PM_SLPSx_L signals???
That points to bad PCH, or some if its signals is not good.
Click to expand...

I can't detect anything at all, but that might just be the tools I have access to not being quick enough so I can't be 100%.

2informaticos said:
Check all 4 (four) RTC signals (page 12).
Click to expand...

PPVRTC_G3H - 3.33v
PCH_CLK32K_RTCX1 - 0.37v
PCH_SRTCRST_L @ 3.33v
RTC_RESET_L - 0.00v

2informaticos said:
Also check PCH_DSWVRMEN and PM_DSW_PWRGD.
Click to expand...

3.24v & 3.41v
 
You must log in or register to reply here.
Top