EEVblog 1672 - JBL REPAIR: You'll never guess the fault!

Repair of a JBL Partybox 310 speaker. Follow along as Dave goes down the repair rabbit hole. Try and guess the exact fault before Dave does, it's a doozy!

Forum:

00:00 - JBL Partybox 310 Speaker fault symptoms and initial failure speculation
02:57 - Teardown
06:23 - Is it a firmware lockup issue?
07:17 - Checking the power switch
09:13 - Main PCB's
10:52 - Hello IT, have you tried turning it off and on again
11:46 - PCB microscope inspection
13:39 - Bench testing and, thou shalt test voltages
16:31 - Looking at the keypad PCB again
17:41 - Replicate the fault using an external PSU
22:55 - Schematic, we have Schematic!
24:14 - The power flow block diagram
28:44 - The penny drops
29:45 - Design TIP
32:04 - Without the schematic I'd be chasing a red herring down a rabbit hole
33:10 - Manual Bypass time to get it working!
34:50 - I called it at the start, but assumed incorrectly
36:33 - OK, let's trace WHERE this fault actually is
37:41 - No, it's can't be, surely not...
39:52 - But WHAT caused it?
42:05 - The repair
44:20 - Assembly back together and testing

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#ElectronicsCreators #Repair #JBL
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https://www.youtube.com/watch?v=WAz-_24-uAI