Acer Travelmate 7520 Backlight gone

Slaanesh

Here goes the story.

A friend of mine has this Acer laptop and they kinda broke the back of the LCD housing, so much so that it would not swivel on it's hinges properly. They got a new back for it but couldn't put it on themselves. I dropped it into a guy who does laptops and he did the job but the brackets for the hinges did not come with the cover so he did a silicon glue job which seemed to do the trick.

I brought the laptop back to my friend, turned it on and the screen did not appear to be working! On closer inspection the screen was working but the backlight was not coming on. I brought it back to the guy and he said that the cables were also slightly damaged and this couldve blown the inverter etc. He said he tried another inverter but that went too. So he just told me where I could get a new cable/inverter. So I picked up the laptop and brought it home.

I opened up the front of the screen to see what I could find. There are 2 wires hanging below the front of the LCD not connected to anything, surely this isn't normal? Anyone know anything about this?

Wires

dazzday

They are the connections for the inverter. The technician should have left the original inverter connected even if he said it was faulty, even for the case so you could identify the serial number etc. Or even check to see there is damage that may have occurred from this repair?

TBH it seems pretty shoddy work if he repaired the unit and neglected to inform the screen was damaged. I am a little confused why he used silicon glue when hinges for majority of models are easy to source? If he knew it was cable failure why would he glue the back bezel back on, knowing it would need to be removed again to replace the cable?

It could be one of a number of things from what you described:

- First off plug the laptop to an external monitor. Although unlikely in your described case, if we get a signal we can rule out the more serious problems such as GPU and 99% of motherboard problems.

- faulty/loose connections. Get back the original inverter and reset every connection to the LCD you see.

- Damaged cable. Damaged hinges could very well mean a damaged cable. However the majority of the time this should be clearly seen. Id be inclined to check the full length of the cable including the portion running up the back of the lcd screen to where it is connected. Even possible it may not be connected correctly there. Replacment cables range up to about ~€40. Replacing this would mean removing the back bezel again, i assume breaking the silicon glue.

- Damaged/stuck/dirty lidswitch. There exists a switch, usually on the screen bezel or power button bezel, that turns the backlight off when you close the lid. In alot of cases these can be come stuck due to dirt etc. See if you can locate it as press it a number if times for any reaction. If you cant locate it, do not worry as the switch may be magnetic or optical in newer models.and therefore quite unlikely to be damaged.

- Faulty inverter. Quite a common problem. Cheapest and easiest item to replace ~€20. However difficult to diagnose as symptoms are the same as faulty backlight.(unless you have a multimeter hand?)

- Faulty backlight. The ccfl bulb (im assuming its not the newer LED screens) could be blown. This is very difficult to replace and in fact most repair shops wont even attempt it. Option here is bo buy a new screen ~€100. Screens are quite easy to replace though, just download the service manual for your build and follow the instructions.

Slaanesh

Thanks for the detailed reply, I'll have a go at some of your suggestions and get back to you.