MacBook Pro A1708 Not turning on, PPBUS G3H shorted to ground repair: Difference between revisions
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(Created page with "{{stub}} {{Repair Guide |Device= |Affects parts= |Needs equipment= |Type= |Difficulty= }} ==Problem description== <nowiki>#</nowiki>incomplete thumb|Example image (Figure 1) -- No image yet. Help expand this page by uploading it! ==Symptoms== *sub 20 ohms on PPBUS_G3H *Not turning on ==Solution== How to find short circuits Inject 1 V (increase if no reaction), watch for hot spots with thermal cam. Usually it's a bad tantalum cap on t...") |
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{{Repair Guide | {{Repair Guide | ||
|Device= | |Device=MacBook Pro A1708 | ||
|Affects parts= | |Affects parts=Motherboard | ||
|Needs equipment= | |Needs equipment=multimeter, soldering iron, soldering station, thermal camera | ||
|Type= | |Type=Soldering | ||
|Difficulty= | |Difficulty=3. Hard | ||
}} | }} | ||
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==Problem description== | ==Problem description== | ||
<nowiki>#</nowiki>incomplete | <nowiki>#</nowiki>incomplete |
Latest revision as of 15:21, 29 October 2023
MacBook Pro A1708 Not turning on, PPBUS G3H shorted to ground repair | |
---|---|
Device | MacBook Pro A1708 |
Affects part(s) | Motherboard |
Needs equipment | multimeter, soldering iron, soldering station, thermal camera |
Difficulty | ◉◉◉◌ Hard |
Type | Soldering |
This article is a stub. You can help Repair Wiki grow by expanding it
Problem description
#incomplete
Symptoms
- sub 20 ohms on PPBUS_G3H
- Not turning on
Solution
Inject 1 V (increase if no reaction), watch for hot spots with thermal cam. Usually it's a bad tantalum cap on the PPBUS_G3H rail.
Example video (Taking 20 V, 0 A. Ethanol used instead of thermal cam with 0.8 V on PPBUS_G3H, resistance between PPBUS_G3H and CPU coil is 3.6 Ω) Example 2: https://www.youtube.com/watch?v=TZsvvUWUInE (Taking 20 V, 20 mA. Bad capacitor located via visual inspection)
Read the resistance from PPBUS_G3H to Vcore coils (coils around CPU/GPU) IF those measure UNDER 1 Ω (0.3–0.8) then you most likely have a direct 12 V short to CPU/GPU. On this board this situation is always a no fix.