(SOLVED) Century Glass Door does not close

Hi everyone 

I just got a century in from a friend that does not play CD, the motor was not spinning at all, it was an easy fix as it was just bad solder.

So I started the unit for general check and the doors close and then open and do not close anymore.

The clamp is OK, I cleaned everything and placed new grease everywhere, so must be electronic.

Anyone had this already ???

It's not the clamp!

There are 3 sensors you need to clean:

1. At the gearbox, there's a little PCB, held by one screw, loosen it, clean the sensor on the pcb. Then clean the gear wheel below with a qtip touched in some cleaning fluid. Turn the gear wheel manually clockwise around and clean it so the sensor is able to tell the difference between the white gear wheel and the black fields on the fear wheel.

2. Unscrew the 4 screws around the CD player cover and remove the whole cover. There's a sensor on the right hand side on top. Clean that one as well.

3. Below the right speaker fret, in the middle of the main PCB there are the last two sensors, two diodes, make sure there's no dust on them as well.

Also, don't forget to clean the Perspex part of the speaker frets so the 2 diodes that you just cleaned in step 3 can see through the Perspex

Dear Root

Thanks, did all what you said (nothing)

I even exchanged the 2 sensors from another Century (same parts numbers), nothing, nothing.

I am checking in the diagrams on PCB 9-5-3 page 2-17 of service manual but there is not much to check

1 Capacitor and then comes the microprocessor

so I think I will have to check the microprocessor, if someone feels I am looking too far please feel free to post

Since the door open and closes once when I plug in the power cord, must be a problem in the timer and I suppose its in the processor

 

P83C528

32kx8 ROM

5 | 2x8 RAM

uPR0CESS0R

PS: What type of sensor is the one of the gear box ???

 

Check fuses & poewer supply to sensor receiver, transmitter, & motor control.

Hi

While checking the voltage on the sensor receiver it suddenly closed the mechanism (the century is kind of nude, no window anymore), Tried to find where was the problem but was not really able to find it.

I just resoldered the 3 wire plug on both side and until now it keeps closing the mechanism.

I did not get how it works, as usually the sensors are hidden. How does the sensor detect the hand ???

To make it work I have to move the sensor receiver aways and when turning it back to the unit it opens the mechanism. 

Drives me crazy that door thing.

When you place the sensor (PCB20- receiver)  in its location the door does not close nor open.

When you place the sensor out of its location upside down doors are opening and closing normally when passing hand above the sensor.

Could it be a problem inside the wires ??? like cut somewhere !!!

I can post pictures if it can help

Might be the wire or the sensor.

Hi Bos00

I will go nuts with that door thing

Changed with a known working sensor, no change

Checked cable continuity OK

Checked voltage 5.0 Volt at sensor between ground and brown wire, 0.600 between the ground and the white wire.

Fooling around created another problem no more 5 volts at sensor, had to change a 10 ohms R, that is the one that changes 5.2 volts to 5.0 volts

Does the same symptom with the working sensor of another century

Keeps working upside down and once inserted it its place : NOTHING .....

Did not find the crying smiley but could use it !!!!!

Hi everyone

Back to the door thing

Did more testing the doors are working when radio is on.

But if I press CD and when the CD does not get recognized the doors stays open.

So the problem is with the CD, but why can it work sometimes a whole day and suddenly I cannot start it anymore.

Bad contact Somewhere ???

Are the doors related with the CD ???

I believe they are related if I remember correctly. They use the same motor for the CD clamper and the sliding glass door. I don't know if this is of any help in this case though.

Well I think that this century has been once in the wrong hands, as the more I look into it, the more I see strange things...

May be someone tried to fix it and did not know what he was doing.(then really not) or too lazy to finish the job.

I found a missing component on a pcb. The one behing the right speaker.

By checking on the service manual the component missing is the TR30 BC337C and has something to do to power the CD when you look at the service manual at Block Diagram for power supply page 2-3.

Unless it is a b&o modification to take it out, but would be strange.

What I cannot explain is : why it worked sometimes ??? as I am not good enough to understand such an electronic datasheet.

Could someone confirm that the TR30 is the culprit and that I lost so much time trying to find the problem on a working CD mech.

Hi

Find a way to start the cd.

Each time it does not start I just have to push slightly on the disk on the opposite side of the laser head, then it is able to make focus on the disk on the first spin, on the second spin I let it go and CD starts to play. Then you can start-stop- change CD it works by itself until it does not work anymore then I restart the process.

This means that the CD is too close to the disk. The CD mech is a VAU1255/21 and I do not know if anything is adjustable.

Anyone on this ???

Hi guys

Well as I said it got into the wrong hands.

The CD problem was the little round holder on the CD mechanism where you place the CD, once I changed it from another unit the CD plays fine. Looks like someone changed it with a different one.

Then the 2 leds behind the speakers could not detect light changes, WHY!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

BECAUSE SOME STUPID GUY PAINTED THE PERSPEX OF THE SPEAKER ON BOTH SIDES...

But as I do not have other one I cannot test I keep you guys updated.

chti59:

....

BECAUSE SOME STUPID GUY PAINTED THE PLASTIC PART OF THE SPEAKER ON BOTH SIDES...

....

 

Lol, hope you can sort it out. Would using paint thinner be an option?

Hi

I used acetone very quickly to soften the paint, then paint thinner. It works but as I could not insist to much with acetone on the infrared filter window.

And both sides were painted, inside ans outside...

I works but not as good as new. I will tell my friend to try to catch some new or used ones on ebay.

I keep checking in the garage some thinner that would not harm plastics and stil clean the paint.

It's not the clamp!

 

 

There are 3 sensors you need to clean:

 

 

1. At the gearbox, there's a little PCB, held by one screw, loosen it, clean the sensor on the pcb. Then clean the gear wheel below with a qtip touched in some cleaning fluid. Turn the gear wheel manually clockwise around and clean it so the sensor is able to tell the difference between the white gear wheel and the black fields on the fear wheel.

 

 

2. Unscrew the 4 screws around the CD player cover and remove the whole cover. There's a sensor on the right hand side on top. Clean that one as well.

 

 

3. Below the right speaker fret, in the middle of the main PCB there are the last two sensors, two diodes, make sure there's no dust on them as well.

 

 

Also, don't forget to clean the Perspex part of the speaker frets so the 2 diodes that you just cleaned in step 3 can see through the Perspex

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Thank you Root! I had a 'wild' Centurydoor. Opens suddenly, closes half, cd-clamp gone crazy. I followed your instructions and the problem has been solved.

Thanx again!