Please help : Repairing a Beosound 9000 with ERR SLG31... making me mad

18 replies

Dear all,

I've been looking at B&O stuff for almost 20 years and I've decided to make the step and buy a complete set. Ok it was out of order but as I'm repairing electronic devices for almost 30 years I've make the deal.

Beolab 8000 were having common problem with the foam and also the problem with the copper no-contact on the power supply PCB (rusted by the wet foam).

Anyway, the Beosound 9000 were not functioning at all. The good point is that it is a MK1 retrofitted with MK3 head. With Beo4 I've checked the error list. With that I manage to repair the IR circuitry (SLG ERR42), have done the calibration and now I can play a CD and it's great... But the sledge refuse to move (It is alive because at the startup it moves from millimeters to find CD1). When I check the error list I have the SLG ERR31.

So I start to dig... The sensor were pretty nasty so I've change the optical sensor but no change. I've made a long cable between the PCB18 and the optical sensor so I can test with my scope easily. I'm lost because I've the correct signals on the input of the processor (after IC9/IC11) and also checked the IC3 and the clock on the IC4. Everything seems correct, I've a switch between 0 and 5v when I click on CD2 and after it tilt to standby mode.

My questions : 

1/ I've remarked that the wheel on the motor is not solid attached and it can move for 1-2° (not loose)

2/ Does the ERR SLG31 mean another thing ?? Regarding the service manual it says that the microprocessor cannot sense puls from PE1... Witch I have...

3/ I've a extra motor PCB but not a PCB18, a PCB35 from a MK3. Regardless the connector witch can be easily purchase, will that works with a mk1 motherboard ?

4/ Maybe a clue... When I disengaged the sledge and put it on CD2 for exemple, when I start the B9000 it goes very quickly to the right and knock the aluminium... Hall effect sensor pb ?

THANKS for reading ... And in advance for your help... I've spent hours and hours on it and I don't know where to search.

Olivier

Does it read cd’s ? Have you cleaned and reattached the glass, an have you run test mode 71 and 73 ?

Does it read cd’s ? Have you cleaned and reattached the glass, an have you run test mode 71 and 73 ?

Does it read cd’s ? Have you cleaned and reattached the glass, an have you run test mode 71 and 73 ?

Hi,

Yes it read CD1 perfectly. Have cleaned and attached the glass but when I go to TM71, it tilt just after closing the glass (when it try to move the sledge...).

Also TM73 is passed. It says APS AJUSTED and just after if I try TM27 I have no error. But if I try a TM71 or to play CD2, same behavior : tilt and SLG 31... 

Service manual says:

-  31: CC sledge pos opto error.
Microprocessor 35IC2 cannot register pulses from 9PE1.

Location: Paris France

It misses pulses from the tachosensor next to the big motor that drives the sledge. 

Location: Utrecht

Quite a challenge to achieve "Less is More" while having the Beovirus.

Yes thanks but as I've said earlier I've tested the pulses and they are ok on the IC2... I've removed the shield and test directly on it. I've a good 0-5v signals on both quad input...

If the sledge “runs” to the next position and shuts off when doing that, then there is a problem with that sensor,  cable or transit through pcb 35.

It’s not capable of counting the pulses correct. 

Location: Utrecht

Quite a challenge to achieve "Less is More" while having the Beovirus.
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