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NEC TG-16/TE/TurboDuo => TG/PCE Repair/Mod Discussion => Topic started by: malikleouf on November 12, 2022, 12:13:56 PM

Title: PCEngine Duo "Please close cover" issue (Fixed)
Post by: malikleouf on November 12, 2022, 12:13:56 PM
Hi everyone,

I bought in August 2022 a Duo CD that needed a recap and some audio fixing (traces and a new OpAmp). I also swapped the lens for a brand new hop-m3. It's been working like a charm until last week when I installed an RGB mod. I was not really happy with the output quality on a Retrotink5x so I attempted to plug it to my PVM to check video quality when the drama happened: it fell off a Kallax (approx 1m - 3ft) and the cd drive broke out of the bottom case  :'(. HuCards were still running fine so I decided to reassemble it.

My issue is that it is now always displaying the "please close cover message" even if I shorted the lid switch. I read that the check is done by IC104 (Pin 33 - AN5 sending a signal through the switch that should be received by PIN 8 - PB5). My questions are:
- what is the error message for a faulty lens? Would I get "please close cover" if I unplug the drive? this would mean I "only" have to replace the lens
- in case IC104 is faulty, is there a place I could by one already programmed or would I need to salvage it from a donor board?
Title: Re: PCEngine Duo "Please close cover" issue
Post by: Necromancer on November 12, 2022, 06:21:30 PM
Oh, lordy, that poor duo!  I can't offer any advice, but I'll keep my fingers crossed that you get it sorted.   :-\
Title: Re: PCEngine Duo "Please close cover" issue
Post by: Keith Courage on November 12, 2022, 08:46:24 PM
Are you shorting the correct pins on the lid switch? Bridging these connections should make the DUO think the lid is closed.

(https://i.postimg.cc/dkJ8phfX/sw401-bottom.jpg) (https://postimg.cc/dkJ8phfX)
Title: Re: PCEngine Duo "Please close cover" issue
Post by: malikleouf on November 13, 2022, 01:50:20 AM
Are you shorting the correct pins on the lid switch? Bridging these connections should make the DUO think the lid is closed.

(https://i.postimg.cc/dkJ8phfX/sw401-bottom.jpg) (https://postimg.cc/dkJ8phfX)

Yup, exactly. I also checked that I had continuity on the connected pads on the right hand side. The switch actually worked fine even before bridging it (got continuity when pressing it)
Title: Re: PCEngine Duo "Please close cover" issue
Post by: malikleouf on November 13, 2022, 01:53:47 AM
Oh, lordy, that poor duo!  I can't offer any advice, but I'll keep my fingers crossed that you get it sorted.   :-\
Thank you! I still hope it will just be about replacing the laser.
Title: Re: PCEngine Duo "Please close cover" issue
Post by: malikleouf on November 15, 2022, 06:25:18 AM
Just received a brand new hop-m3 and error message remains. Next step is for me to see if I can still a working D78C14GF from a donor board.
Title: Re: PCEngine Duo "Please close cover" issue (Fixed)
Post by: malikleouf on November 21, 2022, 02:47:40 AM
I managed to grab a D78C14GF from a dead Duo-R and my Turbo Duo is back to life. I now noticed low CD volume though (which I didn't have before) but that should be easily fixable.