Dead TurboExpress

[OldRover]

Welp, I got my dead one in the mail today. Inside the unit is extensive corrosion of the controller board. This shouldn't be enough to cause the unit to fry out completely, but nat suggested it might be a blown fuse. This seems to be the black box right below the adapter input. Problem is, it doesn't look like a fuse at all, and I have no idea what the frig to do with it. Any ideas on how to fix the damn thing?

[nat]

This is what I would do...(BTW, if you don't feel like doing this you can send it to me and I'll play around with it.)

Clean any corrosion you can find off the board(s). I would remove the shielding too and make sure things are kosher with the components hidden underneath.

If something caused the unit to short out, the fuse surely would have caught this before the PCB was damaged electrically.

A run through the dishwasher wouldn't be a bad idea either. Once things are clean, try to power it up. If you get nothing, bypass the fuse (the black component I identified earlier is the fuse, despite the fact it doesn't appear to be) by adding a jumper wire connecting both legs of the fuse assembly.

Try to power it up again. If you get power, you know the fuse is bad, and you can replace it (or just leave it with the jumper wire in place).

If you still do not get power, my money is that one (or more) of the capacitors in the power circuit is toast.

[OldRover]

Had to get rid of some of that rubbery crap, but I was able to test the continuity of the leads. Both check out fine. The issue lies deeper, apparently.

[nat]

Do you get a backlight when you turn it on? Or nothing at all?

My money is on a bad cap somewhere.

[OldRover]

No backlight. I even put the multimeter to the backlight jack...no power. If I got a backlight, I could narrow it down further, but that's a nada.

[turbokon]

Have you tried powering it with an AC plug or Battery?  I had one a few years ago which was from ebay and the seller said it didn't power up.  I pop in the battery, sure enough it didn't power up.  Luckily I already had another express with the AC plug.  Pop in the plug, it works.  I assumed that there is an IC switch to swith power consumption from the AC plug to the battery source and vice versa.  I just jump the battery connection to where the ac input is and it work with battery from then on.  I just had to make sure that the batterys weren't in there when I use the AC Plug.

[OldRover]

So far I've only used the AC adapter, as I don't have enough batteries kicking around to test it. But I'll pick up a set of AA's tomorrow.

[turbokon]

Did you ever got the TE to power up?  I just did a TE video and sound fixed where it only powerup with AC.  The owner didn't want me to jump the battery connection to the AC jack area.

[OldRover]

No, I've not been able to revive it yet, as I've not had the chance to mess with it further. The unit is quite literally dead. It's likely bad solder points on the mainboard, as there is no power to the LCD backlight. The power inlets are all fine though, so it's not a question of receiving power...that would be an easy fix if it was. I'll mess with it again when I have enough free time...might end up just resoldering the whole mainboard.

[channelmaniac]

Guys,

Excuse me for asking what may seem like a dumb question - I don't have a TE.

Does the power jack have 2 pins or 3 pins?

If it has 3 pins then the power jack has a built in switch which will disconnect the batteries. If it's a 2 pin then there's a circuit somewhere that switches it.

The reason I ask is that if someone plugs an oversized power plug in and forces it in it will bend the side connection and could bend it enough to not reconnect the batteries when the plug is removed.

RJ

[OldRover]

2 pins. It's a pretty standard barrel size, really. The voltage requirements are just pretty specific.

[Duo_R]

Rover did you ever find out what was up with this one? Is it just junked?

[Duo_R]

Rover is the fuse a black box that has a coil in it? Have you tried checking the 7805 regulator?