Why won't monitor turn on after computer "lid" is opened?

Is it possible to have somebody test either the logic board or display board to see whether either or both are damaged. Buying parts can add up quickly. I'm looking at your suggestion on using the terminal command pmset.

Thanks for your help.

The terminal command pmset didn't help.

This accident happened about 7 months ago. At the time, I let the computer air dry and then opened it up to clean with isopropyl alcohol. I thought I was doing a good job of cleaning.

I took it into the Apple store and they opened it up and said there was still liquid (coffee) residue in a couple of spots inside the computer. They said that the computer would degrade with time, as you say, and to spend my money on a new laptop rather than on a repair. Factoring in the price of parts and labor, I could see their point.

In the meantime, the liquid damaged Macbook Air sits on my desk with the lid open, and it's been used everyday for the last several months by my wife. Honestly, it works fine with no apparent issues with our typical day-to-day usage (email, internet, word-processing), other than refusing to awaken when the lid is opened.

I have not taken it to anyone other than the Apple store. Would a thorough cleaning by a reputable repair shop be a good first step?

@rickmandle - Someone with good Mac repair skills should be able to clean and fix your system.

Thanks, I'll try to find somebody.