1.6 Crystal install problem

[Wolfski]

Scenario is 1.6 Crystal XB with a 2.6 mod... it was self install by one of my customers but was handed to me stating "I soldered it all in.. it was working OK but then it just stopped"

The box was fragging and it would not even boot to the flash backup on the mod...... so i opened it up for an inspection....
the install was OK but not good by my standards... absolutely flooded with flux around the pin header ... so i cleaned it up and resoldered the header points... LPC rebuild on the backside was also OK but used much bigger gauge wire than I would have chosen so i replaced that as well !
powered it back up same symptoms...

next move back to basics... removed the mod totally... still frags...!
checked all the points were clear and no solder splash anywhere... looked as clean as a whistle...!

then i noticed that the install had left pin 6 of the header intact whilst still connecting to the alt 5V... wonder if this may have fried something.... its justa failing to find a bios image either in modded or stock config....

have been over the board with magnifying glass and multimeter and it all looks and tests out fine...

anyone got any other ideas I can try out??

thanks in advance

Wolfski

 

[prsplayer]

i just went through modding my xbox 1.6 and i donno what happened to the xbox u have but u might want to try a different chip to see if somethig did fry on the old chip also u might want to check the power supply to see if it gets power.

 

[Fantmx]

The 2.6 doesn't have a backup bios. I would put that chip in a working modded box and see what happens.

 

[Wolfski]

prsplayer...
it wont start up with all the mod bit removed.. suggest onboard BIOS dead/erased?? maybe...

fantmx...
The chip runs fine in my personal box..! i was a bit wary about trying it... in case it screwed mine too.... but it was OK....

Any more ideas guys ..... ? I've double checked the PSU output.. all the voltage regs... lost for ideas now.... anyone got a full schematic ... (yeah right !!)

 

[Big_Whoopin]

It is something on the motherboard itself, which you are aware of. When checking traces that had soldering done nearby, did you check that there was continuity not only from point a to point b on one side of the board, but through the board to another point as well? While a trace could check out fine independently on the top and bottom of the board, if the cylinder that carries the connection through the board got messed up it may not complete the circuit. It is a long shot that this is what happened, but it is something worth looking into.

Only other ideas I can think of is that something managed to wipe/toast the on-board BIOS (possible, but I think unlikely) or that there is still a broken trace or solder splash that you can't find somewhere.

Oh, one other thought... the customer isn't giving you the whole story and they (possibly without even knowing it) goofed it up somehow. "Yeah, the car was running fine and then the engine just died." (neglecting to mention that it has been 15K+ miles since the last time the oil was changed, or even checked.) Food for thought.

At this point I would recommend that they start shopping for a replacement mobo.

-Whoopin'