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A1990 820-01041-07 no power
- Thread starter hgoncalves
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hgoncalves
Active member
Hi,
Just realize (It wasen't before) that PP1V8_SSD0 is shorted and her C8732 was a bit lose and his pad is gone (probably damaged when replacing the nand). Is C8732 critical?
I can't see anything hot in the thermal cam, even consuming 0.460A with 1V.
PP2V5_NAND_SSD0 has 0.387 in diode reading and seams ok.
Can I increase the voltage to 1.5V or what should I check from here?
Just realize (It wasen't before) that PP1V8_SSD0 is shorted and her C8732 was a bit lose and his pad is gone (probably damaged when replacing the nand). Is C8732 critical?
I can't see anything hot in the thermal cam, even consuming 0.460A with 1V.
PP2V5_NAND_SSD0 has 0.387 in diode reading and seams ok.
Can I increase the voltage to 1.5V or what should I check from here?
MLB should start without C8732.
However, is probably better to replace it.
You can increase the voltage until 20% more of nominal voltage; almost 2.2V in this case.
However, is probably better to replace it.
You can increase the voltage until 20% more of nominal voltage; almost 2.2V in this case.
hgoncalves
Active member
I can't see nothing hot, even injecting 2.2V.
What else can i do?
What else can i do?
"PP1V8_SSD0 is shorted"
Is, or not???
Exact ohm value?
Is, or not???
Exact ohm value?
hgoncalves
Active member
Hi.
Yes it is.
PP1V8_SSD0 has 0.3 ohm to ground
Yes it is.
PP1V8_SSD0 has 0.3 ohm to ground
With pure short, even 1V should generate very high current; at least 3A, for 0.3 ohm.
Set PSU amp limit to max first...
Set PSU amp limit to max first...
hgoncalves
Active member
Hi.
Even with no amp limit, it reaches 1.2A with 2.2V, but I can't see anything hot on the thermal cam.
Even with no amp limit, it reaches 1.2A with 2.2V, but I can't see anything hot on the thermal cam.
Then you have more than 0.3 ohm resistance to ground.
Or you lose power on the cables; use thicker ones.
Less than 3W will not cause enough heat to detect culprit with the fingers.
Or you lose power on the cables; use thicker ones.
Less than 3W will not cause enough heat to detect culprit with the fingers.