Playstation One, SCPH-1001 No BOOT

Hey guys, I need some guidance.

I tried searching google and the forums, but I could not find any information regarding the problem I am having with my PSX.

Basically, when I turn on my system, I get nothing on the screen. Without a disc it does not go into the disc/memory card menu. And when I do have a disc installed, the disc spins at up to 1x speed.

I should say that the PSX has not been used for several months unplugged and it has a 7-wire modchip.

I did remove the mod chip and it did not help my situation.

Does anyone have any idea where I should start? Bad motherboard? Bad fuse?

Video:

 

Knowing very little about ps1 repair, I'd say check that the power supply board is outputting the voltages that it's supposed to. I can hardly read this but I believe that the two voltages it should output are 3.5V and 8V. In addition, maybe give the board a heatgun reflow if you have one (only if you are confident in doing so). Did it work fine before going into storage?

 

It is possible that you have a short - the board is possibly grounding to the metal shield or a foreign object is present somewhere. You could try to isolate the board from the shield and see if you can boot to a BIOS screen.

A stuck reset button could leave the system in limbo, however I would also assume (assume!) that the disc wouldn't spin if that were a problem.

As one other check - you may want to examine all of the former solder points for the modchip and make sure that any IC legs or components that wires were soldered to are still making contact with their default locations on the PCB. The modchip gurus would know more about possible failures in that area - I am just shooting the breeze on possible diagnostics.

 

take a look at the AV port and see if there is any corrosion or the contacts are dull , it's possible they need a good clean. Also wiggle the cable where it connects to the PSX.

 

Likely this... My PSone would turn on, no video or any output of any kind.

You can try a place a piece of paper between the board and shielding and see if that works.

@Bad_Ad84 knows a lot about Playstation modchips, he probably knows some other symptoms.

 

The TV gets some sync signals (it switches off the "AV" icon) and the CD spins.
That means you can focus on power distribution to the various chips.
Check all the fuses on the board for continuity.

 

Thanks for the replies.

After taking out the multimeter, the 8 volt output reads at a maximum 7.5 volts. Seems too low...

 

Probably a blown fuse on the 3.5V line. Due to the way the regulation works reduced load on the 3.5V line will cause the 8V line to drop.