Acer Aspire 5920 making strange noises after spill.

A few weeks ago I spilled green tea (no milk or sugar) on the desk around my Acer Aspire 5920 laptop. The tea went into the back left quarter of the machine, mainly through the ventilation holes and the ports on the left side. I removed the battery, drained the liquid, and let the machine dry out thoroughly. Since then the machine has worked fine. However, it occasionally makes strange noises, especially on start up. It's a fizzing/popping noise, in short bursts, like static. It sounds as if it's coming from the loudspeaker.

Please, does anyone know the machine well enough to diagnose the fault? Only the components in the back left quarter of the machine got wet. Could there still be water in there? Is the noise a sign of a serious problem? What can I do to fix it? As I said, the spill happened several weeks ago, and, apart from the noise, the machine works fine.

I'd be very grateful for advice.

 

My guess is there is still some moisture in there. Did you take the cover off the bottom of the laptop and let it dry out that way? Those sounds may be a sign of impending failure of something on the PCB (Printed Circuit Board) such as a transistor or capacitor or something of that nature. However I am not an electronics engineer by any means...im just giving you some ideas.

The fact that the computer still works means something wasnt fatally damaged when you initially spilled the tea and you did the right thing by taking the battery out and letting it dry.

(THIS WAS A LINK TO THE SERVICE MANUAL)
thats a link to the service manual. It may be more helpful than I am

Good luck!

 

Once a PCB is liquid damaged (speaking as an electronics engineer) it's bad news. Contamination always remains and due to an electroylitic action eats it's way into the fine copper tracks and component leads. Multilayer PCBS are worse. It gets under components too.
Strangely the best course of action ( not easy I know ) can be to remove the PCB and wash with a foam cleaner, use a soft brush and rinse well, but this has to be done immediately and no backup battery or cap has to be in place either. The slightest voltage causes a reaction. Then dry completely.
I have done this countless times on anything from remotes to whole TV chassis, with 100% success, but once the damage is done you have problems.

 

Thanks mooler and Mooly -- that's very helpful (though alarming!).

I did take the bottom cover off to let it dry, but I didn't do any washing. Would it still be worth trying washing? And is it possible to pinpoint which components might need attention, please? (As I said, only the back left quarter of the machine got wet.)

I've noticed is that the noise tends to occur at and just after start up. The noise stops once the machine has been on for a while. Is that relevant?

Thanks again.

 

I recko'n the tea might have got into your fans bearing....hence the noise when you start up the machine.

Just a thought...

Cheers

 

Thanks for the suggestion, TeeJay 44. I wondered about the fan myself. It was one of the components that got wet. However, the noise sounds more electronic than mechanical. It's like static on a radio (a fizz-pop sound) and it's quite loud.

Incidentally, I seem to remember that the noise occurred immediately after the spill happened, before I could turn off the machine (it was running at time). Does that give a clue?

 

Any affected parts usually look whiteish or greenish, like a bloom on them.

 

Thanks Mooly. That's very helpful.

 

I've been listening closely, and I'm pretty confident the noise is coming from the loudspeaker (at the front, on the left, below the keyboard). Could it be a loose connection (perhaps caused by manhandling the machine after the spill)?

 

Anything is possible ! Try poking the PCB with it powered up.
As I say, I've worked on countless "spillage" problems and it sounds a typical symptom that starts to become apparent in the days afterwards. Components literally begin to corrode away.