Hi,
I’m troubleshooting a BeoLab 14 subwoofer which produces no sound. I bought the unit from an auction, so history is not known to me. Immediately after power-up with an audio signal in, the status LED starts flashing green and the unit stays in this state. When audio signal is disconnected, led goes red for some 10 seconds before turning off.
For green blinking led, service manual states that it is in software update mode, how can I possibly verify this? This makes me think the LED is infact blinking some strange orange-like colour instead of green. I have worked through the service manual troubleshooting steps for orange and so far I have checked the following:
- Woofer voice coil: 3.7 Ω – seems OK
- NTC (PCB48): ~500 kΩ at room temperature – seems OK
- PCB68 switch panel and its connections have been checked
- Power supply +48 V is present
- +15 V and −15 V are both present (actual values ~-16V and ~+14,5V)
The interesting part is PCB01 / J104.
With J104 connected:
- J104 pin 4: 0 V (I believe this should be 3V?)
- J104 pin 5: ~1.2 V
With J104 disconnected from PCB01, measurement at the cable end:
- pin 1: −15 V
- pin 3: +15 V
- pin 4: 0 V
- pin 5: ~3.7 V
Any advice on what to look at? Audio signal is confirmed to DIN plug, unfortunately I only have one Powerlink cable, but a simple beep test shows positive for that.
.
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