CDP-C500M Drawer Won’t Open Troubleshooting and Repair

The CDP-C500M loading tray not opening was a new fault I recently encountered on this model. The owner had already spent over one hundred pounds having it repaired at the Sony repair facility; however the problem was still there. At first, it was intermittent, but then became permanent.

Pressing the tray OPEN/CLOSE button at the front would not present the CD loading tray. There was a definite noise of the motor but the tray appeared stuck. At first I thought that perhaps the drive belt may be slipping, however as I was to find out later that this CD player uses a tractor belt.

Removing the top cover was simple as there were obvious looking screws around the back and sides. With the unit powered, I could see that pressing the tray OPEN/CLOSE button resulted in the loading tray revolving instead. The unit starts by checking all five of the CD bays, and then reports "NO Disc". At first, I thought that the laser had failed, however I noticed that the laser platform had not risen up towards the CD. The platform was too far down and therefore the laser focusing could not detect the CD. It therefore simply shuffled from one CD position to another searching for a CD.

The next logical step was to check the mechanism that moves the laser platform. In this model, they use a single motor for opening and closing the drawer tray, and raising or lowering the laser platform. The laser platform is the "Optical Pick-up Block BU-5C" part in the manual. This platform has the laser assembly and two motors. All of that has to move UP when the drawer closes.

Usually when you have one motor performing two functions simultaneously that is where the problems tends to occur due to gears losing synchronisation. In this mechanism, when the tray is coming out, a single motor drives a cogwheel mechanism that lowers the laser platform and simultaneously opens the drawer tray.

After some clever lateral thinking and investigation (scratching my head like a chimp), I managed to track the fault to a broken hinge pivot, which is responsible for holding the laser platform at one end. I am not sure what was there originally, however there may have been a clip, because the factory would have installed one end of the pivot into the hole, and the other end would have required a plastic clip to secure the pivot.

The broken pivot was the reason why the platform was not rising, and it was the reason why the drawer was not opening, because in the (flopped) position, the necessary cogwheels do not engage correctly.

There was a piece of rubber, which I removed to make room for my makeshift engineering.

All I needed was a piece of soft plastic to go over the pivot part to secure it. I managed to find a plastic wire retainer, which seemed to be the correct dimensions. I also used hot melt glue from a glue gun to secure the plastic in place. Once the glue had hardened, it was securing the pivot robustly and the problem was solved!

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