Re: Macbook Air 820-00165 Not turning on
This turned out to be C2950 shorted which also killed U8000.
Merc
Member
Last Activity: 03-16-2025, 02:55 PM
Joined: 01-26-2015
Location: Tupelo, MS
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Re: Macbook Air 820-00165 Not turning on
PM_PCH_SYS_PWROK= 0V
Does the PCH require this to be high before it will put out valid signals?Leave a comment:
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Re: Macbook Air 820-00165 Not turning on
SMC_CLK32K is presentLeave a comment:
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Re: Macbook Air 820-00165 Not turning on
PM_RSMRST_L = 3.3V
PM_PWRBTN_L = 3.41V
PM_SLP_S4_L = 84k to ground
PM_SLP_S5_L = 31k to groundLeave a comment:
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Re: Macbook Air 820-00165 Not turning on
PP5V_S4RS3 = 1.14V
I suppose this points back to the PP5V_S4RS3_EN line which comes from PM_SLP_S4_L?Last edited by Merc; 10-29-2019, 11:33 PM.Leave a comment:
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Re: Macbook Air 820-00165 Not turning on
Pvp1v05_sus=1.05v
pvp3v3_sus=3.33vLeave a comment:
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Re: Macbook Air 820-00165 Not turning on
CPU area. Paste was silver and looked fresh....Leave a comment:
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Re: Macbook Air 820-00165 Not turning on
PM_SLP_SUS_L = 3.32V
PM_SLP_S5_L = 0.75V
PM_SLP_S4_L = 0.93V
Taking heatsink off of CPU...Leave a comment:
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Re: Macbook Air 820-00165 Not turning on
P5vs4rs3_en = 0.9vLeave a comment:
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Re: Macbook Air 820-00165 Not turning on
Here is charger....Leave a comment:
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Re: Macbook Air 820-00165 Not turning on
Yes I believe it is genuine Magsafe 2. No adapter.
PP5V_S4RS3 = 1.15V checking on L7520. This voltage rises slowly to 1.15V after I connect the charger. Takes a couple of seconds.Leave a comment:
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Re: Macbook Air 820-00165 Not turning on
I don't know much of the machine's history. I bought it broken from eBay. The listing claimed it was working and suddenly died one day. It also said the keyboard was fully functional up until the laptop stopped working.
SMC_PM_G2_EN = 3.42V
PP5V_S5 = 5.0V
There was another 5V rail that was missing. I'll have to search for it.
Thanks piernovLeave a comment:
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Macbook Air 820-00165 Not turning on
This is my first Macbook repair. No signs of liquid damage.
Laptop does not power on. I have a 45W Magsafe 2 charger. When I connect it, the light turns green for a second and then amber.
PPBUS_G3H = 8.6V
PP3V42_G3H = 3.42V
No 5V signals are present. There does not appear to be a short on the 5V rails. No signs of life with board out of chassis so no keyboard or other peripherals connected.
What do I check next? -
Re: No Power Dell U2410 Monitor
During power-on, the signal on CN851 pin 1 goes from 4.68V down to 0V for 300ms. It then goes up to 3.48V and holds there. During this same time CN851 pin 14 (5V) goes from 5V down to 3.76 then back up to 5V and holds there. I'll try to attach a picture....Leave a comment:
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Re: No Power Dell U2410 Monitor
I also have a dead U2410, however, mine occasionally works. I have had it on several times while working on it and I have taken voltage measurements at CN851 and CN852. When mine is working, I have 5.15V on pins 11-14 on CN851. When it quits, there will be 5V until I hit the power button and then it will drop to 3.7V. At that point, I have to unplug it for a minute and try again. So the 3.7V reading may not indicate a bad firmware or dead micro. I'll post more as I dig deeper.
MercLeave a comment:
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Re: Another 50PJ350 Supply Problem
I have two 22ohm 10W ordered. I'll put those in and test it for a while before sending on. Set is too heavy to haul back and forth.
I think I saw your video if you posted the schematic you drew. Thanks.
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Another 50PJ350 Supply Problem
Repairing for my niece. Turn on and I hear the relays, screen flashes, cuts off.
I find one of the two 22 ohm resistors on power supply board is open. I temporarily outboard some power resistors to see it it works. It does. Let it run. Order new 22ohm 5W. Install, test and send on its way. It's DOA at her house.
Second try. I get it back. Same 22ohm is open again. I order a kit from eBay with resistors, regulator, diode.... Install and it works again. I keep at home this time turning it on and off and then just letting it run some.
After 2-3 days I go turn... -
Re: New Members - please post your introductions here
Hello all. Since I lurk a lot I decided to join. Lots of good info.
MercLeave a comment:
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