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3400c screen dark and fan noise
Posted by: timoog on 2023-07-07 08:22:01
Hi, my 3400c has started some strange behaviour, the screen backlight will go off and the fan comes on, usually just a few seconds sometimes 30-60s. Most often after start up then less frequently. The screen is still active can just about make out icons, windows etc. Any ideas what's up or experience of this?

cheers all
Posted by: Nixontheknight on 2023-07-07 09:18:52
Hi, my 3400c has started some strange behaviour, the screen backlight will go off and the fan comes on, usually just a few seconds sometimes 30-60s. Most often after start up then less frequently. The screen is still active can just about make out icons, windows etc. Any ideas what's up or experience of this?

cheers all
I'm no expert on powerbooks, but that's probably a sign of dying CCFLs
Posted by: 3lectr1cPPC on 2023-07-07 21:52:58
With the other issues I’d say otherwise. Your DC power board is likely on the fritz, or possibly the inverter board. Have you removed the leaky PRAM battery? Have you recapped it?
Posted by: timoog on 2023-07-10 01:30:46
Thanks both. I've not recapped the power board, I've seen it can be a problem and thought it might be related, so will start there. cheers!
Posted by: techknight on 2023-07-20 10:20:18
Did you leave the PRAM battery in there to corrode all over everything? its hidden and this is the symptom when it eats out the vias on the motherboard. I already lost a machine to this.
Posted by: timoog on 2023-07-23 04:52:18
yow! Hope it’s not that 🤞 I took the original out when I got it going but did replace it with a similar one, will check it later
Posted by: timoog on 2023-07-23 13:10:20
Thanks @techknight took the new battery out, all seems ok no sign of leakage or damage on the board. Any other thoughts welcomed
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