PC engine Duo-RX plays hu-cards but get either pink, green or cyan screen for CD

kakutolives · 05/29/2018, 12:06 AM

Hi Guys,

I just recently got a Duo-RX for cheap at a local game store. they were selling it with the issue of being able to play hu-cards but it shows a cyan, pink or green screen if there is no card in the hucard slot. Does anyone have any ideas of where to start looking on the board for this sort of issue?

SignOfZeta · 05/29/2018, 11:38 AM

So that's where it ended up.

Presumably it won't run System Cards from the slot either? I can't remember...some guy had this issue a while back. I assume he lives in your town.

kakutolives · 05/29/2018, 11:05 PM

i ordered a system card on the mail. see if i get any results. if it works that way, ill call myself lucky and use it that way.

Keith Courage · 06/01/2018, 07:38 AM

Sounds like a bad traces or bad chip on the motherboard to me. I'd get in touch with thesteve here in the forums and send it to him for repair.

fredJ · 06/21/2018, 09:48 AM

I came to the forum because I have the same problem.

It doesn't work with system cards either. It just says "Please wait" with a system card but nothing happens. It can't even detect if the lid is closed. Can you give a link to the other thread about this?

Are there any chips that could case the problem that we know? It is in pretty good condition otherwise. Since this is now the third unit with the same problem, maybe there is some common solution.

SignOfZeta · 06/21/2018, 11:52 AM

You have a different problem. If it says "Please Wait..." then you don't have an issue loading the card at all like the OP. Also if it says "Please Wait" then and not "Please Set Disc" then obviously the door switch works.

What you have is an actual CDROM loading issue, totally different. I'd start a new thread for it.

It sounds like you are new to the system. My advice is to go to YouTube and watch some videos of Duos in action to learn what normal operation is, then you can compare what you have.

If you want to see if the door switch is working, try playing the disc with it open and with it shut. See? Diagnosis is fun!

fredJ · 06/21/2018, 03:06 PM

You are wrong. The OP has not tested with a System Card.

If the door switch is open, it will say "please close". If it thinks it is closed, the light will flash as it attempts to read. As it is now, the CD part simply seems unresponsive. My guess is that the OP has the same issue.

System Cards will always start, even on a first gen PC Engine with no CD ROM attachment. But they will get stuck at the "please wait" screen.

SignOfZeta · 06/21/2018, 05:52 PM

Does your machine not load it's own BIOS? That's the current issue the OP has. He hasn't gotten as far as you yet, as far as we know.

You may indeed have the same problem, but we won't know until he gets a System Card. Please, both of you, we need more info. I'm assuming these are systems that have been messed with in the past. Did you ever see the system work? What does it look like inside? How long have you had it? Has it ever worked?

If there are any mods or repairs I'd look real close in that area or for fuckups. Solder drips, anything crimped buged or glued. This is a VERY uncommon problem and all three instances I've heard of it were in the last year, and yes that does make me wonder if we're even taking about three different Duos. If these are three virgin RXs we're talking about that all have this problem it would be very surprising.

Jenshonkan · 07/19/2018, 03:34 PM

Hi

This is my first post on this forum.

I have the same kind of problem with a pc engine duo r. It plays hu cards but if I start it with out hu card I just get a white screen. The CD-ROM unit is completely dead like it gets no power. I have also tried with a cd rom hu card but nothing. It is like the cd rom part of the duo is not there.

Can any one give me some pointers?

I have looked over the main board but cannot see any thing wrong.

Thx in advance

/br jenshonkan

Keith Courage · 07/19/2018, 10:04 PM

1st thing to check is if both 7805 voltage regulators work. Check with a multi-meter to see if both put out 5V

KoSLoW · 07/20/2018, 01:36 AM

Exactly the same on my duo white screen without hu card. I opened a new topic hours ago

Jenshonkan · 07/20/2018, 03:34 AM

Thx for the replay.

I have measured around the board and the 7805 gives 5v to the board. And the actual board looks spotless. So I am starting to think the worst. What ic chip is the one to start looking at? Or maybe i should give up?

Keith Courage · 07/20/2018, 07:13 AM

Did you check both of the 7805 regulators? There is also the possibility of a bad connection or trace under the board near the power input jack. Start testing traces to make sure all is good there. I've come across that a few times now.

Another problem area on DUO-R/RX consoles are the traces for the hu card slot. If any one of those have a bad trace then that can also cause the white screen when turned on if no game is inserted. So turn the board over and start checking the traces that go to the card slot pins.

If the card slot pins test good then I would just message thesteve here from the forums for help and or send it to him for repair. He is a pro when it comes to chip replacement and or fixing bad connections for them. Even though I repair a lot of these systems myself, I know when to pass a system off to someone with more experience in certain areas than I.

thesteve · 08/05/2018, 03:43 PM

ok lost of the same issue here sounds like
look for missing address pulses to the D91317GD (almost every time)
IC520 could be bad, but will often also keep cards from working (check pulses at slot with cart out)

kakutolives · 08/10/2018, 01:44 AM

i got it to work under some rather odd circumstances. i had the same issue with the arcade card. interesting part?
among all the trouble shooting (and 30-40 reboots) i left it on for over 20 minutes on a pink screen (must have been on for about an hour)
i had to go take care of some business and when i came back, the lens was making clicking noises(even with a pink screen)
i rebooted it and i got a bios screen! but it was freezing on the press run screen.
after that i kept rebooting it about half a dozen times and i actually got it to go in game!. i finished dracula x from beginning to end on that session.
I know electronics do not normally behave this way (even if they are having bad capacitor problems, erratic behavior wouldnt "flush" after just rebooting)
it has been working ever since for the last 6 weeks or so. anybody have any idea what the heck could cause this???

kakutolives · 08/10/2018, 01:45 AM

oh forgot to add, arcade card worked after i got it running. sorry for the double post.

thesteve · 08/10/2018, 06:58 AM

you have an intermittent connection somewhere
i have see ones that wont boot till they have been on a while