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#339719 - 24/11/2010 07:08 Mark 2 power failure?
juenk
journeyman

Registered: 12/01/2002
Posts: 84
Loc: Waardenburg, The Netherlands
Yesterday I tried to use my spare Empeg (Riocar Mark 2A) again after a year of non-usage. It does not power up at all (no display messages, no hard drive starting up). The network light on the back is flashing blue very fast, same for the lights of the lighting buttons on the front (very dim though).
I checked the power supply, it works OK with the other Empeg so the supply seems OK to me.
I connected it via serial to Hyperterminal, nothing at all displayed.

Any suggestions what to check and/or how to fix?

Jelle


Edited by juenk (24/11/2010 08:08)
_________________________
Empeg M2A Blue # 010101908 80Gb
Empeg M2A Blue # 030102771 with backlight buttons - Need repair (IDE cable connection on main board) - volunteers?

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#339723 - 24/11/2010 12:30 Re: Mark 2 power failure? [Re: juenk]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 14478
Loc: Canada
Unplug the drive and try again.

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#339724 - 24/11/2010 12:44 Re: Mark 2 power failure? [Re: mlord]
juenk
journeyman

Registered: 12/01/2002
Posts: 84
Loc: Waardenburg, The Netherlands
Forgot to tell, already tried that, with same result.
_________________________
Empeg M2A Blue # 010101908 80Gb
Empeg M2A Blue # 030102771 with backlight buttons - Need repair (IDE cable connection on main board) - volunteers?

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#339737 - 24/11/2010 16:57 Re: Mark 2 power failure? [Re: juenk]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31565
Loc: Seattle, WA
The power supply is a known-good power supply of the correct type?

There isn't a physical problem inside the unit like a loose screw that got stuck against a critical power system component?

Display board cable is plugged in correctly (i.e., not off-by-one-pin)?
_________________________
Tony Fabris

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#339762 - 25/11/2010 19:10 Re: Mark 2 power failure? [Re: tfabris]
juenk
journeyman

Registered: 12/01/2002
Posts: 84
Loc: Waardenburg, The Netherlands
Thanks for all the input. Just tried to check a few points mentioned, however with 2 kids around that didn't work out that easy - it will have to wait until the weekend:)
_________________________
Empeg M2A Blue # 010101908 80Gb
Empeg M2A Blue # 030102771 with backlight buttons - Need repair (IDE cable connection on main board) - volunteers?

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#339885 - 29/11/2010 11:31 Re: Mark 2 power failure? [Re: juenk]
juenk
journeyman

Registered: 12/01/2002
Posts: 84
Loc: Waardenburg, The Netherlands
I think I've found a reasonable explanation, see picture below. Cause unknown, might be (as Tony indicted) caused by some loose metal part inside?

Any suggestions to fix, or is replacement Empeg a better alternative?



Jelle


Attachments
P1020335c.JPG (73 downloads)
Description: damaged empeg


_________________________
Empeg M2A Blue # 010101908 80Gb
Empeg M2A Blue # 030102771 with backlight buttons - Need repair (IDE cable connection on main board) - volunteers?

Top
#339888 - 29/11/2010 12:52 Re: Mark 2 power failure? [Re: juenk]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 14478
Loc: Canada
Wow.. looks like you have/had a wiring issue with the in-car docking sled.

I don't have a Mk2a unit opened up here right now, but I do have a Mk2 open --> the black/burned component at far left is a 1.2Kohm resistor in my Mk2, and the blown-away item was a 0-ohm resistor.

EDIT: MMmm.. in my Mk2, those four contacts (the two for each burnt part) are all earthed/grounded. Which, to me, suggests that the in-car wiring may have been wired backwards, trying to feed +12V through the ground wiring.. BOOM!

Cheers


Edited by mlord (29/11/2010 13:08)

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#339890 - 29/11/2010 12:57 Re: Mark 2 power failure? [Re: juenk]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 14478
Loc: Canada
Originally Posted By: juenk
Any suggestions to fix, or is replacement Empeg a better alternative?

If the damage (burning/melting) extends inside the multilayer circuit board, then it will be very tricky to repair.

You could try the simple thing of replacing the two obviously blown components, and then powering it up using the indoor AC-adapter. Most likely, they will blow again, but you could get lucky, and have almost nothing to lose.

If that doesn't fix it, then I recommend putting the unit aside for use as "spare parts", and trying to purchase a replacement unit. This should be cheaper than paying for a difficult repair job, and the unit may be "beyond repair" already regardless.

But first I'd try the suggestion of replacing the two blown parts, just for fun. smile

-ml

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#339891 - 29/11/2010 13:00 Re: Mark 2 power failure? [Re: mlord]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 14478
Loc: Canada
Something else to do first --> get some mostly-pure alcohol, or similar cleaning fluid, and swap away all of the burn marks in the area. If the circuit board cleans up really well that way, then the damage may not be very bad.

But if it stays very black in colour, that's an indication of possible major damage.

Cheers

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#339892 - 29/11/2010 13:13 Re: Mark 2 power failure? [Re: mlord]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 14478
Loc: Canada
Heh.. after examining my own Mk2 even more closely, I now believe it was assembled incorrectly --> the 1.2Kohm resistor should probably have been another zero-ohm resistor. smile

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#339913 - 29/11/2010 19:18 Re: Mark 2 power failure? [Re: mlord]
lectric
pooh-bah

Registered: 20/01/2002
Posts: 2085
Loc: New Orleans, LA
OK, I have to ask. Isn't a 0 ohm resistor like, a wire?

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#339914 - 29/11/2010 19:20 Re: Mark 2 power failure? [Re: lectric]
tman
carpal tunnel

Registered: 24/12/2001
Posts: 5528
Originally Posted By: lectric
OK, I have to ask. Isn't a 0 ohm resistor like, a wire?

Yup. Its handy to have it in a regular resistor form factor for when you need to bridge two points when you're doing automated assembly.

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#339920 - 29/11/2010 21:53 Re: Mark 2 power failure? [Re: lectric]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31565
Loc: Seattle, WA
Originally Posted By: lectric
OK, I have to ask. Isn't a 0 ohm resistor like, a wire?


In this case, more like a fuse. smile
_________________________
Tony Fabris

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#339928 - 30/11/2010 05:28 Re: Mark 2 power failure? [Re: mlord]
Ross Wellington
enthusiast

Registered: 21/02/2006
Posts: 325
Hi,

I checked one of my Mk2a boards and it has a 1.2k (marked with a 122), and a zero-Ohm (marked 000), in the locations that Mark originally had indicated. The 1.2k is closest to the screw hole, the Zero-Ohm is next to it on the right.


In case you were wondering, the 122 marking on the resistor is 12 with 2 zeros. So that would be 1200 Ohms. There are 1000 Ohms in a k-Ohm. So the resistor has a value of 1.2k Ohms.

The same can be said for the larger yellow "block" looking solid Tantalum capacitors. A marking of 226 is 22 with 6 zeros. That is in pico-Farad (pF). So it would be 22,000,000 pF. There are 1,000,000 pF in a micro-Farad. So the capacitor has a value of 22uF. I know, geek stuff, get back on topic...


Mark is right, clean it up, snap another picture and maybe there is hope.

After the board is cleaned up, some measurements can be made with an Digital multi-meter to see some of the extent of the damage.

Since there isn't information on the layer stack-up and trace routing of the Printed Circuit Board, if it has caused excessive heat and has gone through the top layer to internal layers, it may not be fixable. Not that anything in that area is likely to be controlled impedance, but if the resin/glass weave separated (exceeding the Glass Transition (Tg) of 120 to 160 Deg C.), and allows adjacent layer routes to touch, it could be flaky, intermittent, or just a complete short. If the layer information was known, sometimes you can drill or open the traces (depends if there are planes - it looks like there is, you can't see through the board - in the same area though), and use wires to correct it.

Too bad that kind of data isn't available, it could be useful in these situations.

Keep hope, after you clean it, we'll know more, there's still a good chance it might be minor.


Ross
_________________________
In SI, a little termination and attention to layout goes a long way. In EMC, without SI, you'll spend 80% of the effort on the last 3dB.

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#339940 - 30/11/2010 13:25 Re: Mark 2 power failure? [Re: tman]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 14478
Loc: Canada
Originally Posted By: tman
Originally Posted By: lectric
OK, I have to ask. Isn't a 0 ohm resistor like, a wire?

Yup. Its handy to have it in a regular resistor form factor for when you need to bridge two points when you're doing automated assembly.

And good board designers add a liberal dose of them on most I/O circuits, so that individual parts of the circuitry can be disabled/corrected easily in the event of a design/layout error.

Cheers

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#339962 - 30/11/2010 15:14 Re: Mark 2 power failure? [Re: juenk]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31565
Loc: Seattle, WA
Originally Posted By: juenk
I think I've found a reasonable explanation, see picture below. Cause unknown, might be (as Tony indicted) caused by some loose metal part inside?


Or possibly caused by a problem in the car wiring... a loose or chafed wire, a crimp that came undone and got grounded, or perhaps even the sled connector is having trouble. If you get the player repaired, make sure to check for these possible issues before you plug it back into the sled.
_________________________
Tony Fabris

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#339995 - 30/11/2010 21:03 Re: Mark 2 power failure? [Re: mlord]
lectric
pooh-bah

Registered: 20/01/2002
Posts: 2085
Loc: New Orleans, LA
Originally Posted By: mlord
Originally Posted By: tman
Originally Posted By: lectric
OK, I have to ask. Isn't a 0 ohm resistor like, a wire?

Yup. Its handy to have it in a regular resistor form factor for when you need to bridge two points when you're doing automated assembly.

And good board designers add a liberal dose of them on most I/O circuits, so that individual parts of the circuitry can be disabled/corrected easily in the event of a design/layout error.

Cheers
Interesting. I couldn't quite get my head around why you would want to interrupt a trace with a more expensive component that doesn't DO anything. But that makes perfect sense now. Modular hardware design. Neat.

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