Gary L. Woodruff wrote:
howdy, I have a pioneer PD-M450 Cd player that would not play disks.
It would load them but and the laser would go in try to focus but the
disk would never spin. I found the plastic lens had fallen out of the
optical assembly and would not stay in when replaced. I ordered a new
optical pickup and replaced the old one. I have the same problem. I
have confirmed that the spindle motor will run with 1.0 vdc supplied.
I do not see any voltage appear at the motor leads while the lens is
trying to focus. Please help, optical pickup was $$$$.

thanks, Gary

The replacement pickup may not work right out of the box because IIRC, it
doesn't come pre-aligned. You'll need to boot it into test mode and use a
scope probe to adjust it. I believe it's called the gradient adjustment.
Might just be easier to do as the previous responders have suggested which
is to carefully glue the lens back on. Make sure whatever glue you use, that
it doesn't fog up the lens!

--
David Farber
David Farber's Service Center
L.A., CA