Bose Lifestyle 650 remote malfunction

[mpa2]

Hi everyone,

I'm trying to fix this RF Bose remote (model nr. 420129) for a friend. After applying supply voltage the display shows the Bose logo, after a short period of time it goes dark and the MCU enters a sleep mode. It wakes up after a key is pressed, the display remains dark all the time after the start up sequence.

Sometimes it can still be paired with the main unit and you can control it for a short period of time, then the unit stops reacting again.

The pcb is clean, there are no signs of corrosion. The voltages look adequate.

I read the dump from the nvram and rewrote it several times without errors, but the problem remains.

Maybe anyone has a working dump I could try? Or other ideas I could do?

Thanks,
Michael

[Diah]

with out Batteries and its cover,,, when you shuttle the remote heavily did you hear noise from inside?

[mpa2]

with out Batteries and its cover,,, when you shuttle the remote heavily did you hear noise from inside?

well, it's completely disassembled now, there were no loose parts inside What kind of noise do you mean?

[Diah]

take a look here

[mpa2]

take a look here

No, it's a different case here. The antenna is just a trace on the pcb. All keys seem to react.

[Diah]

show please the downside

[Diah]

other things this is hand work nor robot !!

[mpa2]

show please the downside

[mpa2]

other things this is hand work nor robot !!

This was me, adding a cap in parallel for testing. Doesn't look that bad in reality

[Diah]

you have one or more keys always in contact..... carefully remove the white keys plate use alcohol up to 90% , clean the conductive lines all with it too let it dry and align the keys sheets back

[mpa2]

Thanks, I will try it tomorrow. I actually tested the frequently used keys and the reaction of the MCU (wake up) was adequate, but I didn't check all of them. I hope I'll get this white stuff off without damaging it.

[Diah]

Thanks, I will try it tomorrow. I actually tested the frequently used keys and the reaction of the MCU (wake up) was adequate, but I didn't check all of them. I hope I'll get this white stuff off without damaging it.

its glue as Mobile glass protection screen

[mpa2]

Unfortunately, this didn't have any effect. All contacts are clean and open. Still the same behavior.

[Diah]

Unfortunately, this didn't have any effect. All contacts are clean and open. Still the same behavior.

this is not enough.. you need to put yours DM in Amp reading in the Red + line and switch on..... remark the pulling of Am at any state even sleep and when you wake it ab

[mpa2]

this is not enough.. you need to put yours DM in Amp reading in the Red + line and switch on..... remark the pulling of Am at any state even sleep and when you wake it ab

Im monitoring the current draw with the lab psu and in addition the mcu sleep/awake state with thermal imaging.

[Diah]

Im monitoring the current draw with the lab psu and in addition the mcu sleep/awake state with thermal imaging.

and did you noticed some unusual draw? by the way did it wake up on all keys

[mpa2]

Yes, after removing the white foil I tested all keys - they are all NO and closing every single one of them causes a wake up. The current draw looks fine for me - about 5 ma on start up, about 3 ma when awake and almost zero when asleep.
I noticed another strange behavior. There a light switch on the buttom side, which turns on LED Backlight of the keypad and also wakes up the MCU. This wakeup works always, the LEDs however sometimes don't react.

[Diah]

Yes, after removing the white foil I tested all keys - they are all NO and closing every single one of them causes a wake up. The current draw looks fine for me - about 5 ma on start up, about 3 ma when awake and almost zero when asleep.
I noticed another strange behavior. There a light switch on the buttom side, which turns on LED Backlight of the keypad and also wakes up the MCU. This wakeup works always, the LEDs however sometimes don't react.

can you show it here with focused clear photo

[mpa2]

can you show it here with focused clear photo

You mean the push button itself?

[Diah]

You mean the push button itself?

just remark it on yours photo which it show all BL working with out pressing any key