Sony CDP-101 spindle motor

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is there someone of you who had repaired this problem ?
when I turn on my CD player SONY CDP-101, the spindle motor spins very fast and spins from turning on the CD player without any chance to stop it.
I have changed IC-201 (CX-193 - disc motor servo) without luck, the IC-201 is OK.
does anyone know the right answer what is wrong?
thank you
When it spins very fast when a CD is inserted, E-F Balance might be off.
This happened to me, whe I tried to align a Sony-based nakamichi player.
Maybe, with a balanced power supply, one supply does not work.
But I am, not a technician.
I was very, very surprised to see one CDP-101 in a shop called "Haus der Musik" in Bonn, Germany.
It was September 2012.
They do not sell used gear and it stood there like they had forgotten to sell it for 30 years. Contacted them later to ask for a price but they never mailed back.
Maybe a chace for you to get a working one...
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I think I forgot to write the spindle motor spins straight from turning on CD player (pressing POWER button). normally from turning on the CD player the spindle motor does not run, then after loading CD in tray and detecting CD the spindle motor begins to spin with constant speed to load TOC and then by pressing PLAY button spins again.
but in my case it spins straight from turning on the CD player without a chance to stop it. it does not depend on if the CD is in the tray or not. it runs and runs
written before hifi_sk's last post...

Manual in German and English, and Sony's own "Troubleshooting Guide", are available at There's a supplement at the end of the service manual with revisions and later circuit mods.

There are a few possible causes of your problem. This machine uses a LED and phototransistor to sense the presence of a disk, so spinning may not be an indication that other parts of the start-up procedure have completed successfully. Was the machine working before this fault appeared? If not, or you don't know, then you should start by making sure as far as you can that the mechanics are properly adjusted and moving freely as shown in the service manual. Then keep following the manual through laser and focus check, until you get to the adjustments that need the machine to be playing, which you can't do if your fault is also present in "adjustment mode".

There is an explanation in the manual of the role of the PLL clock, and in particular its free-running frequency, but I don't quite follow what it means. Normally, the disk speeds up until the data rate matches the PLL frequency. Initially, until the PLL locks, the free-running frequency is used. Until it locks onto what, I wonder, and when? Anyway, you might check the PLL is running.

Somewere on the net there's a little list of common faults and solutions, made IIRC by a service engineer, but I've lost the link.

My CDP101 spins fast at the end of its "getting totally lost" procedure, initiated occasionally when searching for distant tracks. Once the disk reaches take-off speed, it lifts it up, flings it forward, and jams it in the opening drawer. Maybe yours starts from the totally lost position. If the chip you just replaced were at fault, the machine should have ejected after 6 seconds.

There's lots of subcircuits involved in the start-up procedure, so unless someone is familiar with this particular problem, I can only suggest that you check power supply voltages and then soldier on through the troubleshooting guide.

There were two failing electrolytics in my power supply, btw. Access is a nightmare. The glue used to stick wires and caps in place has become corrosive, so you should remove it as much as you can, and particularly away from metal. It can eat the tin off a pin all the way through the board and out the other side of the joint, so watch out for that whilst you're in there.
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Check the four supplies are correct at the motor itself. Confirm that the motor control input pin is at zero volts. If those are OK and the motor still spins then there is an internal problem in the hall effect motor.

Q202 should be on with the collector at zero volts DC. In that condition the motor is braked.
many thanks for your advices. i am busy in work, have a family but evenings when little princess sleep i can for a while measuring on CDP.
so i observed today almost everything around the IC-201 and i measure these :
on IC-201:
-pin 6 is 5,4V instead of 0V
-pin 21 is 5,7V instead of 0V
-pin 23 is is 0V instead of 1,3V
-pin 24 is 0V instead of of 0,4V
-in all other pins is voltage OK

i have measure even 2 pins i suggest is in relation with spindle motor driver on IC-101:
-pin 31 (DISC STOP) - 4,15V OK
-pin 19 (BRAKE) - 0,66V OK

voltage on Q202:
-collector - 0V OK
-base - 0,66V OK

voltage on Q201:
-collector - 0V OK
-base - 0,66V OK

i dont know what else, next on the target is IC-202 or IC-203
voltage on supplies of servo amp board on pins of CNJ1 are OK but on +/- 10V pins is :
-14,5V on pin where should be -10V
+13V on pin where should be +10V
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Some of the supplies are unregulated which is why the -/+10 volt rails appear high. That's normal.

You have zero on collector of Q202. That means that the fault is to the right of that transistor. Pin 7 of IC202 should also be zero. If it is, and the motor has the four supplies I mentioned earlier correctly applied, then the motor is faulty.
hello again,
today measurement on BSL motor board the supplies are OK:
- (-14,12V) on -10V
- (+12,5V) on +10V
- (-11,8V) on -12V
- (+11,9V) on +12V
- BSL RED (pin7 on IC-202) - (-9,4V)

also on pin7 on IC-202 is -9,4V on inpunts opamp (pin 5,6) is voltage OK (0V)
do you think the IC-202 is fault?
Pin6 of ic201 should be 0V when player is stopped, and 5.2V when playing.

If pin5 ic202 is 0V, then the output voltage will reduce until the current into R230 matches that coming out of R227.

This immediate cause of the problem does not necessarily incriminate ic201, which may be getting bad input.

Are you sure that spinning is the only thing going on? If the start-up procedure is also attempting to complete, then that pin6 might change as a result of some other fault.

That's why I wonder whether the machine was working before this fault occured. If the laser's dead there's probably no point in continuing, for example. Likewise if it's an abandoned basket-case with multiple defects.
Joined 2007
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Its a strange result, the numbers not quite making sense. You have to measure pin 6 of IC201 as Plastic mentions above, which should be zero in stop mode. Its pin 6 (of the opamp) reading zero that doesn't ring true given that the output is hard toward the negative rail.
No, it doesn't add up. If pin5 of ic202 is 0V then it seems to me that pin6 becomes a virtual ground. The 540uA of current arriving from R227 must all pass through R230, because any passing through R229 would result in a non-zero voltage at the inverting input. But then the output would be -30V. So I assume there are actually voltages at the inputs, but perhaps below the range used for the measurement. Or AC perhaps.

All that may turn out to be OK, eventually. For the moment, if pin6 ic202 is connected to ground, that should defeat the signal from pin6 ic201, and stop the motor. Then attention should shift to the inputs to ic201

If the machine is oblivious to its motor problem, it should try to complete its start-up procedure if a disk is present. Once it fails to complete because it can't read, it should eject after a few seconds.

The manual suggests a preliminary check for focus operation and laser output, by blocking the light to the disk-detecting phototransistor at start-up. It would be reassuring if that test were done before trying to unravel the ic201 problem.

Also, if anyone can find that list of service points I mentioned, it may be that failure of ic201 was a common fault. I've looked and looked because I want it myself...
I really like this heavy machine,but sometimes I miss the RESET button :)
I have once again measured the voltage on disconnected connector CNJ36 from BSL board,the voltage is the same so the BSL board is OK. There is one pin called BSL, this is output from pin7 opamp of IC-202 (as you written) this voltage I thing is regulator for the right speed and rotation of spindle motor. I have measured -9,44V, regullar voltage should be not over 5V (I only think) and thats the reason the motor spins too fast and maybe wrong direction.
On inputs of these opamp pin5 and 6 of IC-202 is the voltage OK. when I take a look on schematic there is only R227,R229,R230 and C210 it could be wrong or IC-202 at all.
But there is wrong voltage on pin6 of IC-201 (5,4V instead of 0V), this pin is an output from "LOGIC" inside of IC-201.
On IC-101 the signal DISC STOP (pin31) is OK 4,15V and signal Brake (pin19) is OK 0.66V.
I do not know how goes the start-up procedure, may be is the process fault and the procedure do not goes to the end and it stucks somwhere in "circle"
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And you have changed IC201 I think.

It can help with faults like this to go around every pin (and I mean every one :)) on the IC with a scope and make sure that whatever is expected really is there.

Worth checking around Q201. With 0.6 volts on the base the AC signal to pin 8 of IC201 should be removed.
Yes you are right, and most important is experiences and skills with elektronics. those I do not have, scope I do not have also. I just tought, it is frequently fault as STK 6922 and it can be easy recovered.
voltage on base of Q201 (0,66V) is correct as in schematic shown
I want to say very very thank you for your patience and good will to help me to solve the problem on distance.
I have measured today the IC-503 with multimeter on 20V DC range with these results:
- pin 27 (RFCK/4) - 0,03V
- pin 14 - 0,6V
- pin 15 - 1,99V
- pin 16 - 1,78V
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