HP DesignJet 500 - Printhead carriage stuck

[sk187]

I am not a plotter tech, just the small office IT guy.

The local engineering supply place will not service a plotter this old so I am looking for help.

We have a older DJ 500 plotter that quit midway through a print.

The printhead carriage assembly is stuck on the far left side of the machine and can move about 3" to the right before getting stuck.

The plotter screen is saying "Open window and check printhead cover is properly closed".

I am not able to see anything without removing the body of the plotter.

Does anyone happen to have any ideas before I start taking this apart?

Thanks!

[Phil B.]

Re: HP DesignJet 500 - Printhead carriage stuck

I am not a plotter tech, just the small office IT guy.

The local engineering supply place will not service a plotter this old so I am looking for help.

We have a older DJ 500 plotter that quit midway through a print.

The printhead carriage assembly is stuck on the far left side of the machine and can move about 3" to the right before getting stuck.

The plotter screen is saying "Open window and check printhead cover is properly closed".

I am not able to see anything without removing the body of the plotter.

Does anyone happen to have any ideas before I start taking this apart?

Thanks!

turn unit off

take a towel moistened with IPA

clean the encoder strip at rear of carriage CAREFULLY.

manually move the carriage to clean the other portion of encoder strip

power up

test

[sk187]

Re: HP DesignJet 500 - Printhead carriage stuck

turn unit off

take a towel moistened with IPA

clean the encoder strip at rear of carriage CAREFULLY.

manually move the carriage to clean the other portion of encoder strip

power up

test

Would a dirty encoder strip make it so I can not even manually move the carriage with the power off?
The carriage moves a few inches by hand and then hits something and you can not move it even really pulling on it.

[Phil B.]

Re: HP DesignJet 500 - Printhead carriage stuck

Would a dirty encoder strip make it so I can not even manually move the carriage with the power off?
The carriage moves a few inches by hand and then hits something and you can not move it even really pulling on it.

check to make sure the door on the carriage assm is LOCKED DOWN

[sk187]

Re: HP DesignJet 500 - Printhead carriage stuck

check to make sure the door on the carriage assm is LOCKED DOWN

I've checked that, opened and closed it several times.

[Phil B.]

Re: HP DesignJet 500 - Printhead carriage stuck

I've checked that, opened and closed it several times.

if the machine is off... you should be able to move the print head you've got something blocking the path.

[sk187]

Re: HP DesignJet 500 - Printhead carriage stuck

if the machine is off... you should be able to move the print head you've got something blocking the path.

Best to just take the body of the printer off and check it out I guess.

[Phil B.]

Re: HP DesignJet 500 - Printhead carriage stuck

Best to just take the body of the printer off and check it out I guess.

you can get a better view if the covers are removed.

[blackcat4866]

Re: HP DesignJet 500 - Printhead carriage stuck

I'm going to take a guess that the carriage belt is shredded, and some of the strands wrapped around the motor pulley. It's not very difficult to change that carriage belt, if that's what you need. =^..^=

[sk187]

Re: HP DesignJet 500 - Printhead carriage stuck

I'm going to take a guess that the carriage belt is shredded, and some of the strands wrapped around the motor pulley. It's not very difficult to change that carriage belt, if that's what you need. =^..^=

Thanks for the help, I will check that out.

[Gift]

Re: HP DesignJet 500 - Printhead carriage stuck

I'm going to take a guess that the carriage belt is shredded, and some of the strands wrapped around the motor pulley. It's not very difficult to change that carriage belt, if that's what you need. =^..^=

My dad owns a DJ500... I'm not a HP tech but I found it pretty good to service. I've changed the maintanance station once and the belt, too (there was a nice youtube video with good instructions available - bought a non OEM belt, so far so good). But iirc a shreddered belt was very obvios to discover and the printer even starts to spill rubber pieces some time before the belt is totally destroyed.

Makes sense to remove the covers and get a better look what's going on - perhaps the carriage assy got stuck with the paper cutter.

[Kiran Otter]

Re: HP DesignJet 500 - Printhead carriage stuck

Check out lpscomputer.com, they sell the belts and have videos on how to do the repair. The trickiest part, is the trailing cable. When you pull it out of the carriage, examine the ends to make sure they aren't coming apart. If they are, do not attempt to reuse them. You have to replace the trailing cable as well. Attached is what a bad trailing cable end looks like. I assume Tim goes over this in his videos since it's a common occurrence.

Kiran

[Kiran Otter]

Re: HP DesignJet 500 - Printhead carriage stuck

And the sort of X-shaped plastic piece that holds down the trailing cable where it meets the carriage will be broken. You can buy one but honestly, if you don't want to spend $18 for a seven cent piece of plastic you can forget about it. I always replace them but I have a bunch of them on-hand.

And don't break the rear bushing on the carriage when putting the carriage back in. It's very easy to catch it on the chassis and snap it off. Tim mentions it in his video.

Attached is a picture of the bushing.

Kiran

[D Hook]

Re: HP DesignJet 500 - Printhead carriage stuck

One other thing to add to Kiran's excellent advice on the trailing cable; when you go to reconnect the trailing cable on the carriage, get down and take a very close look at the "socket" the cable goes into and note that it sits at a very slight angle forward. (Look close before you disconnect it.) So that when you go to reconnect the cables, you'll want to have it at the correct angle to easily go in smoothly and not damage the ends of the cable. I've had trouble in the past reconnecting the trailing cable to the carriage until I realized it sits at a slight angle to the carriage. Once I saw that, I never had trouble connecting again. Trailing cables aren't expensive but they delay the reassembly and are a real PIA to connect correctly. If you only have to disconnect one end, it will save you a lot of time and hair pulling.