Amiga 4000d IDE problems

[Audun]

Hey folks, I have recently gotten hold of an Amiga 4000 which was functioning optimally a couple of months ago. It's a standard edition with a 030 cpu, 3.1 roms, mediator with full package (sb, tv tuner, network card, voodoo, cf adapter)  - so what happened was, all of a sudden the CF card stopped functioning in the machine (but works on others). And now whenever I connect an IDE device (any IDE device except floppy) to the controller, the powerled keeps flashing like it's guruing and won't boot at all. When I disconnect all the IDE stuff except the floppydrive, it boots fine from floppy (although very slow before it starts, but I hear that is normal on 4ks).

Here's what I tried:
I checked for corrosion on the mainboard, leaked battery acid etc, none found. I removed the mediator with no result. I tried switching cpu boards, adding a buddha IDE controller - still the same crap. I'm completely lost as to what the cause may be. The ram also seems to work perfectly when I boot with WB 3.1 floppies.

Does anyone have a clue what could be the source of the problem? Please, I would very much appreciate any input I could get!

[stopthegop]

First thing, try a different cable.  Make sure its a standard 40 pin cable, not the keyed variety.

Try it with just one IDE device instead of two.  If using only one device then that device has to be jumpered as a master.  If using a CDRom or DVDRom & a harddrive then the harddrive has to be the master and the removable media drive (whatever it is) has to be the slave.  If using two harddrives, then the bigger of the two should be the master as well as the boot drive (assuming you don't use SCSI as well..).  If using two removable media drives, it doesn't matter so much as long as one is the master and the other is slave.  Even if you have a four way splitter, the same basic rules apply.  

[Audun]

Thank you, stopthegop, these are good suggestions. I have already considered this though, and I have isolated single IDE units with no success. Before that I had also eliminated jumper settings as the cause of any problems.

The issue itself occurred with no apparent change in hardware settings, it just seemed to happen at random. So I remain puzzled as to what the cause may be. Would you happen to have any other suggestions? I am very grateful for any input here.

[Zac67]

- check PSU output voltages
- check electrolytic capacitors for leakage

[Audun]

Good ideas, there is no leakage from the capacitators - but I will have to wait to confirm the psu as I don't have any means of checking the output, nor a spare psu to work with :\ Good suggestion though, thank you.

[magnetic]

zac

what is the procedure for checking the caps? Using a multimeter what readings should you get?

magnetic

[rkauer]

 Don't bother to check the caps!

 Simply change all of'hem! Is unexpensive and far more reliable change all those little hell-spawns than tweaking around the mobo.:pissed:

 I change ALL electrolythics each 3 years from all my Miggys. :-D