Replaced most of all other caps (expecially all the 100uF 16V that had almost all high ESR) and now it works. Replaced also some others around the amplifier because no audio issue too.
This board is really crap.
Thank you for the tips!
Jacksoft
Member
Last Activity: 03-19-2025, 11:47 AM
Joined: 02-03-2011
Location:
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Yeah, I suspected this. Tomorrow I'll give a look and let you know.
Thank you so much for now!Leave a comment:
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Damn! I totally forgot about ripple! I was fooled by the fact that voltages looked good on every line!
In fact about two caps where 10 to 14Ohm in ESR test!
I've replaced all of them you signed in red, thank you!
By the way the TV shows another problem now (dunno if it was present before because the TV was off by some years).
About every tested input (Analog TV (just white noise), AV, SCART, HDMI) shows bad glitches excepts for the OSD and the VGA input that works perfectly.
In first place I thought it was the PI3HDMI412FTBE switch IC but it shows on...Leave a comment:
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Samsung 225MW EEPROM bootloop
Hi all,
I got an old Samsung 225MW TV with BN41-00825 motherboard.
Since the TV has a buzzer when it starts it makes a beep. The main problem is that the TV goes in a sort of bootloop and beeps every 2-3 seconds.
So I attached the VGA UART cable and read the debug data using a RT809H programmer:
According to the Service Manual all the voltages looks good, so I made a backup of the internal flash and all the EEPROMs (1 Settings + 3 EDID) and cleaned the EEPROM.
Now the TV boots but it's stuck on VGA. If I try to change the source it goes to TV, restarts... -
Yes it would be the best, but they're becoming rare and expensive
The only thing I could suggest is to see on the service manual, if any, if there's a specific code because I don't know if the thermal sensor changes between the fans.Leave a comment:
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After days of headhache I found that original fans have a Thermometer inside instead of a Tachimeter!
So I made a little bypass by adding a 100k trimmer to drop the sensor voltage to about 1.20V.
The TV worked perfectly for hours with fans at maximum rate (9V)
[ATTACH=JSON]{"data-align":"none","data-size":"thumb","data-attachmentid":3157492}[/ATTACH] [ATTACH=JSON]{"data-align":"none","data-size":"thumb","data-attachmentid":3157491}[/ATTACH]After days of headhache I found...Leave a comment:
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Panasonic Viera TX-P46G10E 11 blink even after fan replacement
Hi all,
I have here a Plasma TV TX-P46G10E that before had a problem where it had issues with 11 blinks (FAN SOS) BEFORE starting normally. After that it works for all day long.
It had some bad cold solder and I remade them all. After I replaced a fan that was half-dead (no RMP signal from the respective pin, but ok with 9V).
Now the TV power up instantly and works perfect... only without the backplate!
If the backplate is placed on the TV shutsdown after about 10min and start blinking with the 11 blinks. If I shutdown and re-powerup it starts blinking after a bunch of... -
Re: PS4 SAB-001 no power after cleanup
Hi guys,
We finally figured out what happened and I'm writing how for who could have my same problem.
A friend of mine gave us a BLOD motherboard for voltage and other stuff references.
This line goes at about 0.90V 0.80Ah (there is another line that goes at about 1.10V 1.30Ah) in powerup/boot.
Our APU works correctly at this values and that was the strange thing, so we started to traceback all around the two mosfet on this line.
In final we found that during the disassembly (or moving the motherboard...Leave a comment:
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PS4 SAB-001 no power after cleanup
Hi everyone,
today we cleaned up from dust a PS4 Fat with SAB-001 motherboard and replaced the thermal paste with Arctic MX-4 (non conductive). Before disassembly the PS4 powered on normally but the fan was just loud because the dust.
We made many PS4 before, without problem and by being delicate in handling them.
Now, that's the strange part.
This PS4, after reassembly, just do a "beep" and immediately shutdown. After testing with another PSU we inspected the motherboard and found a blown fuse (F5104). Picture attached with some characters... -
Re: A2159 no power on
Oh, well. We've just plugged the mb to check the current from the external adapter (1.27Ah) and it started up...
What could been?
Now we have just to figure why SSD is not recognized.Leave a comment:
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A2159 no power on
Good morning everyone.
We have a MacBook A2159 with 820-01598 motherboard that was in contact with liquids (Cola) and had troubles to power on (of course).
After a good cleaning it power on without problems but does not recognize the SSD (that are on-board chips).
Since the T2 grid was contamined with the Cola we opened it up with the dremel and cleaned inside there too.
We made no damage, since we used a tiny blade, but now the mac does not power on anymore.
Looking at other threads here almost all the main voltages are present (if I haven't missed other important... -
Re: Apple A1466 power on issue
Hi all,
SORRY for the huuuuuuge delay!
We tried to replace the U7870 from a working donor board (but with BGA problems) and still the same. We checked all the caps, removed the U8040 but still short, removed also the Q1920 and no luck. We thought the CPU was dead (we tested with just the MagSafe board connected).
Fully reassebled the Mac back and after some days... It started works again.
Now we don't understand how this is possible. We checked almost anything and seems there was no extra solder that could caouse a short....Last edited by Jacksoft; 06-10-2023, 05:21 PM.Leave a comment:
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Re: Apple A1466 power on issue
PP3V42_G3H is 3.42V
PPBUS_G3H is 8.60V
MagSafe LED color is orange.
CPU and SSD are active with about 60°C and the fan is off.
EDIT: U7870 gets hot too, but voltages seems present.Last edited by Jacksoft; 05-23-2023, 10:34 AM.Leave a comment:
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Re: Apple A1466 power on issue
Yes, the 3.42 is present.
But now, don't know why, the Mac does not power on at all.
To be more precise:
If on battery, thermal camera show heat on CPU and SSD and after 3-4 seconds cools down.
If AC plugged in, thermal camera show a persistent heat on CPU and SSD but the Mac still not bootup.
No fan spin-up.Leave a comment:
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Re: Apple A1502 very slow after liquid damage
Hi,
I'm sorry for the late reply.
In final we found that the problem is related to some BGA issue (not sure if under SMC or CPU), because without any screw around CPU/SMC the problem is not present and AST pass all test (ever the longer one).
Probably the Mac was also dropped, or the short damaged a solder ball and this happens.
Thank you.Leave a comment:
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Apple A1466 power on issue
Hi all,
I have a MacBook A1466 with 820-00165-A with a strange issue.
The Mac power on and runs perfectly, AST in EFI mode passes all the tests (even the full longer test), but if you leave the Mac off, and without the power adapter connected, for about two days without powering it on and using it, it will not power on anymore (battery have enough charge).
Already did an SMC reset but the issue still persist.
What could I check?
Thank you. -
Apple A1502 very slow after liquid damage
Hi all,
I have a trouble with a MacBook A1502 with 820-4924-A motherboard after it became in contact with some liquid (Picture attached, that's the only point where oxyde were).
I know that is a very critical point because that traces goes to the SMC and to the CPU.
The most oxyde is on XDP_CPU_PWRBTN_L and XDP_CPU_VCCST_PWRGD trace.
The PC is REALLY slow in any operation, but the fan works normally (it turns on only when the CPU is really stressed) and the CPU does not get warm, like it's running in "low power mode".
We made a check with AST in EFI... -
Re: Apple A1708 charging problem
The new MOSFET has been arrived and replaced the old one and the Mac now goes on 20V on both ports, charges and powers on!
Leave a comment:
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Re: Apple A1708 charging problem
Hi,
while we wait the new mosfet I've made some measurement by looking at steps on logi.wiki (CD3215 Bootup Sequence), and it fails at step 3.
HV_GATE1 = 1.7V
HV_GATE2 = 5V
PPDCIN_G3H = 1.6V
TBA_VDDA = 0V
PM_EN_P3V3_G3H = 0.4V
I've not continued in measuring, since this fails.
We removed the mosfet and the HV_GATE1 and 2 are respectively 6V and 11V.
In the attached picture there is the port that can't reach the 20V status....Leave a comment:
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Re: Apple A1708 charging problem
Thank you. I'll let you know what we've discovered.Leave a comment:
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