Marantz CC67 CD Player won't spin disk

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#3
How does it recognize a disc? Shouldn't it start turning the CD and if it can read something like the TOC it considers it a valid disc? So if it doesn't turn the disc, it never recognizes it.
I have a similar problem here with a Technics SL-PJ26A that I gotta look into. I suppose it's a mechanical fault. The first thing I'm gonny try is to look that the spindle motor isn't burned out.
 
#4
Does the lens perform a focus search routine and move up and down 3 or more times when the tray is closed ?
If no you might have problems.
If yes, have you cleaned the lens.
Is the turntable free.
Has it failed of it's own accord or were you working or modding it ?
What is the optical unit in these.

And after that it's proper fault finding time. Measure ALL rails and make sure no safety resistors etc are open circuit.
 
#5
Ok,

It failed on its own without help from me.

The lens moves up and down as I can hear it.

The turntable moves freely without a problem.

I changed the motor thinking it might be the problem. I had a known good

motor of the same part number.

I don't know what optical unit it has in it but will try to find out.
 
#9
So was the laser unit bad?


I assume it had a problem of some sort. The motor that I put in worked when taken off the unit and having voltage applied to it. It would not work however on that particular sled. After I replaced the laser/motor sled everything worked as it should.
 
#11
EBM_dude said:
How does it recognize a disc? Shouldn't it start turning the CD and if it can read something like the TOC it considers it a valid disc? So if it doesn't turn the disc, it never recognizes it.
I have a similar problem here with a Technics SL-PJ26A that I gotta look into. I suppose it's a mechanical fault. The first thing I'm gonny try is to look that the spindle motor isn't burned out.
Click to expand...

The sequence of events following closing of tray is,

1. Laser is illuminated. At this point you can usually calculate the laser current by reference to a voltage drop across a specific resistor. The current is critical and optical units such as the KSS series (Not the CDM's etc) have the exact value as part of the pickup serial number eg 458754125561 means 56.1ma (last three digits) If it's higher than specified by 10 to 15% the laser is "bad". As lasers deteriorate the auto power control alters the current to compensate (to keep the optical output constant).

2. The disc servo starts a focus search routine. The lens is driven up and down usually three times. The servo is looking to find "focus" on the disc, and it's much easier to do that on a stationery object so the disc doesn't at this point rotate.

3. If focus is found the disc motor is then run to approximately the correct speed at which point both the focus and tracking servos are active. To see if this point is reached check the FOK (Focus OK point)

4. The data coming off the disc is then phase locked to a reference frequency.

Spindle motors are a major issue, can be worth a drop of oil and (disconnect first) applying say 9 volts to "burn" off any contamination from the commutator.
 
#13
One more thing to consider... check the height of the spindle motor wheel for lack of the proper name for it. The CD sits on it in order to spin. Anyway sometimes it can end up lower causing the CD to bind and not to spin. I had almost given up on the second sled assy when I heard it try to spin several times. I adjusted it up and it works after that.
 
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