Chosen Solution
HK speaker isn’t powering on. I’ve confirmed that the power supply is outputting the required voltage (18.50). The Power board inside the unit (which has the DC, USB, and audio jack) is only outputting between .1 and 2V to the main system. The only components on this board are 4 resistors and a capacitor. If one of those goes bad would this stop the unit from working? If it isn’t one of those passives, any suggestions as to where to look to find what went bad and repair the unit?
I use my HK on battery and turn off after red light blinking (even I notice battery was very short this time). After 3 hours I put on AC but no charging light. Try to turn on but still nothing, like it’s died. I try to restart with all kind combination buttons and everything. At least I push all 5 buttons at same time and start charging and finally turn on. Amazing…
Press volume up button and down button same time on 20sec Then press the power button….
Board level repairs are near impossible without a schematic and an engineer level of knowledge to calculate nominal values at different measurement points. You can measure resistance of certain components and compare to their color coded value but as often as not will end up destroying a sensitive IC chip through back probing- the meter sends a voltage to measure resistance and it gets to a pin on the chip not designed for it. And with SMT components replacement is impossible without specialized micro tools anyway. When a power supply board goes bad about all you can do is inspect for bad caps, which will appear swollen/leaking, and do a visual with light and magnifier on any through hole solder joints. Usually input jacks or large wires to other boards. I have repaired a number of PC LCD monitors with bad power supplies on the illumination section that had visually obvious bad caps. Mfr (usually viewsonic) used low bidder substandard caps. $9 in parts an hour labor and good for life. Never hurts to take em apart and have a look. If you want to get crazy and the boards happen to be that lead free euro safe solder which is prone to separation, cracking and tin whiskers, you can try throwing it in an oven at about 425 degrees or careful direction of a heat gun. Basically resoldering the whole board in a similar way as the SMT components originally were. Many XBOX360 owners reported success with that in repairing RROD issues. However that is obviously an unorthodox unprofessional method with as much chance of utterly destroying your equipment as fixing it. Last resort before the round file.
I have a similar problem with our H/K Play & Go Wireless. The problem in our case could be isolated to simply a bad power connection at the back of the unit, which connects to the 18 Volt source. All kinds of strange problems occurs such as not being found as a BT unit, faulty connections, also that it may work at low volume but you get dropouts at higher volume settings. It appeared as if the unit has power but not enough amps to drive it - requires quite a lot of amps this little monster :) Our temporary fix this evening is to just make sure the connector has som physical drag to the side to ensure sufficiently low contact resistance. This fixed the problem 100% so I’m sure this is the problem. I’ll fix this tomorrow by disassembling the unit and replace/adjust or re-solder the power terminals at the power connector.
This is what I’ve found from messing around with it. Pressing all five buttons at once: Seems to reset the power (only way to bring it back from no lights at all - assuming plugged in). Hold “bluetooth” and “-” button: Changes between lower and higher bass. Hold “bluetooth” and “+” button: The speaker says “three, four”… then the lights flash across and the speaker completely shuts off and becomes unresponsive. Hold “-” and “+” button: Seems to mute the audio, disconnecting the bluetooth (but the bluetooth light is still lit). Unresponsive after. Holding “-” and “+” again turns off the bluetooth light and it becomes responsive again. Holding “power” and “+/-” buttons: No apparent effect. Holding “+” and “play/pause” buttons: Resets speaker and removes all bluetooth connections (doesn’t work if no lights).
