New Zealand Vintage Computer Forums

Hi. I have just unearthed my Dad's old Amiga computer. This brings back memories of wonderful games, puzzles, academic tests and other wonderful activities. I would now like to resurrect the computer. I have plugged everything in (I think) but unsuprisingly it doesn't work. There is power but no drive light. Anyone out there, living in Nelson, who would like to visit me and give me a hand with this? Thanks, Dawn

Don't live anything like near Nelson but let's see if we can figure out what your Amiga is up to. First things first, what model is it, and what accessories are you using? What are you using as a display?

By 'power but no drive light', do you mean that of the two lights, the power one comes on, but the drive one doesn't? If I remember correctly (my memory of Amigas is very stale), I would expect:

- The drive should sit there seeking once every two seconds or so, looking for a disk, though I don't think the drive light came on until it found one,
- The power light should be static green, though I think it was a two-colour LED, and could show red if something went wrong during the startup process

Even without a monitor you could probably tell a bit about how healthy an A500 is (assuming it is an A500, original poster wasn't clear on that one). I used to work at a Commodore service centre mainly on A500s in the early 90s, disappointing how little I remember of that!

Maybe try fiddling with the couple of buttons on the back of the monitor, (assuming it's a standard commodore monitor) to find the right input selection, given the computer is powering on you ought to see something on the monitor regardless if whether it reads disks or not (a picture of a hand holding a floppy is what you need to see).

I'd have to go start mine to confirm but I'm 99% certain the A500 doesn't actually light up the drive light unless it's actively reading/writing.

What you should see is the power light come in dimly as the machine POSTs, and go full bright once the machine has concluded its POST. Once this happens the floppy drive should seek back and forth, then click every few seconds until a disk is inserted. If you have no drive noise then you're in a bad way - electrically it's generally CIAs failing that kills the floppy, the A500 has two of these. Otherwise it could be the drive mechanism itself that's at fault.

Don't worry about the power LED colour, it's irrelevant - they weren't dual colour, but they DID use a variety of colours on the A500 production run. Earlier models tend to have red LEDs, later models have green LEDs. If the machine crashes for some reason the power LED fluctuates brightness rather than colour. You get used to that particular trait... piece of software fails to load, power light flickers, GURU MEDITATION.

But before any of that discussion we need to make sure you can get a picture or all the loading software in the universe is wasted

Carcenomy wrote:I'd have to go start mine to confirm but I'm 99% certain the A500 doesn't actually light up the drive light unless it's actively reading/writing.

Going from memory I think it does if there is no disk in the drive. It keeps checking to see if one is there.

My memory was becoming cloudy with 'does it light up? doesn't it light up?'

So I went and started my A500 up. It's a middle-aged variant, red LEDs, Kickstart 1.3, no A501 at present. No drive LED unless there's a disk present, but it does give the seek and clicking which every A500 I've seen does regardless of LEDs, so if it's making no noise whatsoever... ruh roh

Thanks all for your responses. Please excuse my complete ignorance on what I am using - I think it is an Amiga 500, the monitor says Commodore, the keyboard says Amiga, then there is a box thing with an on/off switch. The keyboard power light is red and flickers, there is no drive light at all. The monitor screen changes from yellow or green to grey but there is no picture of a hand with a floppy disk. From memory I think this should be on the screen. So is this an uh oh?

Flickering power light would classify as 'uh oh'.
I'm not an Amiga expert, but my first guess would be either a faulty PSU or a few of the capacitors inside the keyboard-unit have dried out a bit (seems to be common with computers that are stored for long periods). My Amiga 600HD does the same thing, but I haven't got around to any proper poking/repairing.

Edit: falco's post below is probably more accurate, mine is flickers like crazy and has no screen output, I forgot about the startup tests.

This sounds like a power up test failure, especially if the power light does a regular on - off - on - off flash. I seem to recall there are ways to tell what's going wrong from the screen colours, but Google might have more info. If that's what it is, it could be any number of causes. First thing I'd do is remove any memory expansion/clock unit from the bottom trapdoor. The batteries on these leak and kill the expansion, which can show the kind of symptoms described, but removing the expansion removes the fault as well. Worth a try (if there is an expansion that is).

Second opening the trapdoor and removing any expansion - most A500s ended up with the A501 expansion, and when they crap out this is exactly what happens. Mine was doing this when I went to check it last night, pulled its 501 out and it came right.

Ed: Check out the Amiga 500 Wikipedia page, appears someone's gone to the good effort of listing the fault screen colour codes so if you do find an A501 in there and yank it out, and it STILL gives you colours... you'll know what's up!

Yellow is a bit of a pain to diagnose, my A1000 resets/cycles on a yellow screen and I haven't managed to fix it yet and run out of chips to swap.
The bad news Dawn, is that it's probably not going to be easy unless removing the A501 expansion does the trick.

If you need a spare a500 motherboard I have a couple.