PowerMac G4 MDD won't start anymore!

[AJKing]

I've got a PowerMac G4 MDD (dual 867), slightly upgraded (2 additional hard-drives, 2gb RAM, lightscribe DVD drive) which was running 10.5.6 beautifully until this past Saturday. My girlfriend shut it down (we rarely do) during a storm and now it won't start back up! The power light turns on while pressing it but it quickly disappears. I've reset the PMU and still nothing.

Any help? Thanks in advance.

 

[adcx64]

Sounds like a bad power supply....

 

[AJKing]

Is there a way I could check before replacing it?

 

[Dave H]

How old is the PRAM battery? They can cause strange problems when they die.

 

[666sheep]

Is there a way I could check before replacing it?

If you have a multimeter, you can check output voltages on PSU->logic board plug. Exactly that same as with PC ATX PSU.

 

[MacintoshMaster]

I think it could either be

1. Bad Plug Socket (Due to the storm)
2. Bad Power Pack

 

[KítscheñÇinqµe]

specific details may give clues. i added a few words to your description.
http://www.google.com/search?q=power+light+turns+on+press+quickly+fade|+disappears+g4+|+powermac
links to posts. many mentioned suspecting a dead psu or battery, but there are some other ideas.

 

[AJKing]

How old is the PRAM battery? They can cause strange problems when they die.

It's the original battery, so 12 years old. I'll look into the multimeter, see if I can pick one up somewhere around here.

 

[Dave H]

It's the original battery, so 12 years old.

They usually last 4-5 years. I'd suggest replacing it.

 

[bizzle]

It's the original battery, so 12 years old. I'll look into the multimeter, see if I can pick one up somewhere around here.

You must have went from 1999 into the future year of 2002 to purchase it and brought it back to 1999 if it's 12 years old.

That machine will run with NO PRAM battery. It's most likely NOT the cause of your issue.

 

[mabaker]

Do try to replace the lil battery. My dual 800 didn’t want to start up properly and since I replaced it it is working a lot better with only sporadic acting up.

 

[AJKing]

You must have went from 1999 into the future year of 2002 to purchase it and brought it back to 1999 if it's 12 years old.

That machine will run with NO PRAM battery. It's most likely NOT the cause of your issue.

These computers were sold in 2002 but a large amount of the hardware is dated 1999. If you've ever looked inside one you'd know.

Thanks to everyone for the help. I'll replace the battery, see what happens. I'm thinking it's not the power supply since the power light still lights up. Just really hoping the logic board is okay.

 

[stroked]

These computers were sold in 2002 but a large amount of the hardware is dated 1999. If you've ever looked inside one you'd know.

Thanks to everyone for the help. I'll replace the battery, see what happens. I'm thinking it's not the power supply since the power light still lights up. Just really hoping the logic board is okay.

There are several circuits in a PSU. Just because a light comes on, doesn't mean your PSU isn't bad.