Dell Latitude E6400 power button and wireless not working or only working intermittently

Question

The power button on the laptop stopped working randomly as of a day or two ago. I can only power the laptop on if its attached to a docking station, on which I can use the power button to turn on/off the laptop. Today the wireless card stopped working (the wifi light does not turn on, even after I turn on the wireless switch).

What is the problem and how can I fix it?

The laptop is about 1 year old. I have not dropped it, but do carry it around a good amount, including docking it/undocking it frequently.

Answer 1

On this model laptop (among others) the wireless switch and power button are integrated into a shared circuit board which is connected to the mother board via a small white ribbon cable in the laptop, so it makes sense that both the power button and wireless are exhibiting signs of failure if there is a problem with this circuit board. If the circuit board has failed it needs to be replaced. There are instructions online for how to replace it, including this youtube video.

In my particular case I noticed that depending on how I held the laptop (or if I jiggled it) occasionally the wireless card would start working again. This told me I probably had a loose cable. Sure enough, I opened up the laptop keyboard and noticed that the white ribbon was loose. I snuggly reinserted the white ribbon cable into its slot on the motherboard and 'clipped' it back into place, and voila, problem solved. The power button and wireless switch are now working perfectly.