Are the little pin connectors in the MagSafe socket and jack, clean?
If any of either side has debris or an obscured connection, this will
prevent adequate electrical contact from being made.
•Apple Portables: Troubleshooting MagSafe adapters - Apple Support
•Mac notebooks: All about batteries - Apple Support
•Intel-Based Apple notebooks: Identifying the right power adapter and power cord - Apple Support
•This also considers - if an update in existing software - may be needed:
http://www.apple.com/batteries/maximizing-performance/
Another connection issue could present itself should the MagSafe
DC-in Board (in computer) has became defective; as this would
require a service for the part to be replaced, if determined so...
The DC-in Board (equivalent) can be looked into, and it may help to see
the iFixit repair guides for MacBook models; find your specific one here:
https://www.ifixit.com/Device/MacBook
{Of course, the basis of most troubleshooting relies on the peripheral
or removable parts, cable, adapter, battery, to be known-good & OK.
So if OWC can pre-check their product before shipping, that'd help.}
Sometimes those SMC and NVRAM resets don't appear to change
anything, they could be performed more than twice without harm.
There could be another hardware issue behind this situation, or
there may be some other problem. Not sure if a detailed look into
the Console logs or the System Profile's power or energy info could
be of much help to a non-professional, who may diagnose from it.
Hopefully the problem will be overcome, perhaps a visit to another
Apple repair specialist, or an AASP with other testing measures?
Good luck & happy computing! 🙂
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