KLH model KD-1220 DVD Player, Disc Tray will not stay open

I am not familiar with that model, but most units have a switch that senses when someone pushes on the tray and then activates the closing action. Could that switch be out of alignment or broken? Just a guess.

Pat

there is generally a crappy leaf type switch to sense with the door is open. try burnishing it with some paper.

does the unit open all the way, then pause and close or just close instantly? It may have no idea when it reached end of travel.

Hi,

The tray opens all the way, then immediately closes.

Regarding the leaf switch or other type, did you notice this part of my post: " Note: I was in consumer electronics service for many years." Don't you think I looked for such a switch?

One thing I forgot to say, I do NOT have a service manual for this unit.

Revised Question:

Did anyone have this exact same problem with this same brand and model DVD player and repaired it?

Thank You in advance, John

I read your original post, and I too did not deduct from it that you were a consumer electronics wiz. If you had been, I thought you would have mentioned that you had checked any switches involved in the tray operation. I think you might be better off taking a deep breath and saying you had checked such items, rather than criticizing someone who was trying to help you.

my

DVD

Is the tray opening part of a single combined cam system with dropping disc from play position , and the reverse, tray in and disc up ? And something slipped out of kilter in the drive train

I first noticed you can't solve a door tray issue, then I noticed you listed no previous troubleshooting steps.

Well, pardon us for trying to help. What you describe is a very common problem with all CD/DVD mechs, and I can't remember ever fixing one of any make or model that wasn't down to a dirty sense switch somewhere in the mech. Maybe you just weren't looking in the right place ?

Then perhaps you need one ...

Arfa

Hi Ken,

I am sorry I did not mention that I looked for such a switch in my original post.

If there is a "switch", it is in a hidden location since I did not disassemble the tray from the rest. Note: I opened the tray all the way, then pulled the plug in my search for a switch.

If I had a SM, I would know what method is used to determine the tray status. John

This sounds like something worth looking into. I've had to remove gears and reset the position of computer CDROM trays before. If you bang the tray too hard, the teeth can slip, confusing the heck out of the unit.

Hi, i'll try to write in english..

some times i've heard about this problem, i know on cdrom readers there is a lever type switch with the lever pushed in one side when tray opens and the other when it closes, if when the user commands to open, the tray reaches the end of the run the board (i think) senses motor's too much current use and revert the direction, i think the switch is a single contact but in some way when the tray closes there is no invertion or maybe the switch has 3 contacts but 2 are common so the "close" contact works, the "open" not.. this sw. is on one side of the tray, if you watch under the bottom side is made like __/'''''''''''''''''''''''''''\___ this... it is on the front, i think. i've been clear?

Bye..

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model

disc

Or due to kids or drunks trying to force open the tray

The reason that this problem happens, is that although we all know that pushing on the tray to close it is a bad idea, manufacturers know that punters are gonna do it. So they arrange for the micro to look at the 'tray open' switch from two points of view. First, they check if the switch contacts close whilst the tray motor is running. When that is true, the tray is open, and the power to the motor is cut. The switch is then monitored for it going open when the motor is not running. When that is true, the motor is run in reverse to close the tray. This allows the tray to be pushed to the point of the switch re-opening, before the motor takes over and finishes the job. This sequence can of course be over-ridden by the open / close button being pressed. This takes priority over the 'motor stopped - tray switch closed' condition that prevailed at the end of the opening sequence.

The problems start when the contacts on the 'tray open' switch get sooty, as they frequently do. So the tray opens, the switch closes, the motor stops, and then the switch momentarily opens again, even though it is firmly mechanically pressed, due to the sooty contacts not making very well. This is immediately seen as the tray having been pushed by the owner, so the system control micro starts to run the motor in reverse. This all happens so quickly that what you get is effectively the tray fully opening, and immediately 'bouncing' back closed.

Although over the years I have come across the odd exception to the mechanical switch scheme, it is by far and away the most commonly used tray management system from all manufacturers, Usually, the switch is an easily visible leaf contact type, mounted somewhere near the front of the deck, but on some mechs, it can be located in much harder to see places. Also, some mechs use miniature plunger switches in all sorts of obscure locations, and still others use either of those switch types, but mounted to the side of - or even under - a mechanical 'cam' that's part of the tray open / close - disc clamping arrangement.

Arfa

Hi, UPDATE:

Well I was wrong. There is a switch, but it is tiny on the left side. You can not see it unless the tray is all the way out. Before, when I pulled the plug, I guess the tray was not all the way our. Note: This is not a leaf type switch but more like a "micro switch", and very small.

Thanks to everyone for your responses.

John