Ouch! This doesn’t sound good!
The SIL indicator blinking five times is a sign the logic board has a problem [https://support.apple.com/guide/mac-help/if-the-sleep-light-flashes-mh21502/mac|If the sleep light flashes on Mac]
[quote]'''If the sleep indicator light flashes during startup'''
If you don’t hear beeps, but the sleep indicator light flashes five times when you start up your Mac or wake it from sleep, your Mac might need service. See Find how to service or repair your Mac.
'''Important:''' If your Mac has a faulty battery, or no battery, and it runs out of power, you could lose unsaved changes. To avoid this, keep your battery charged.[/quote]
Time to visit an independent Mac repair shop (one with micro-soldering skills)[br]
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