Replaced LCD Inverter

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February 18th, 2011, 06:56 AM
kleefarr

Replaced LCD Inverter

Hi guys,

I replaced an LCD Inverter on a Dell Studio 1535 earlier.
Seemed like the problem was fixed straight away, but after 10-15 mins screen goes blank again and will only come back once restarted.

Diagnostics tell me that the LCD Inverter Cable is missing.
Have checked all connections but same problem.

Edit 1: There is slight flicker as well which isn't noticeable when the brightness is turned up.

Edit 2: It's just gone off again, but the external monitor I have connected is still displaying fine.

Edit 3: The display also comes back on when you close and open the lid.

Edit 4: Tested LCD Lid switch. Goes into standby when a magnet positioned over switch and resumes when removed. So I guess it's not the switch. ??

Edit 5: Same outcome in Safe Mode. However, with the external monitor attached, when laptop display goes off you can switch to the external monitor and get the display and when you switch back to laptop monitor the display comes back on.

Is it likely that the LCD inverter is faulty?

Kevin
February 18th, 2011, 07:13 AM
CCT

Could be a broken wire(s) in the cable from repetitive bending.
February 18th, 2011, 07:20 AM
kleefarr

But then why would the display come on and then stay on for 10 mins, but then dim and go off with out being moved?

It's just gone off again, but the external monitor I have connected is still displaying fine.

All new info added to original post
February 19th, 2011, 07:01 AM
kleefarr

New info added.

Any more ideas guys??

Board?
Backlight?
Or faulty LCD Inverter?
February 19th, 2011, 11:36 AM
kleefarr

Could it be a power problem?

See edit 5.
February 19th, 2011, 11:47 AM
slgrieb

I think the simplest explanation that would seem to fit the symptoms would be that you got a defective inverter. If you didn't have these issues before the old inverter failed, and they have only appeared with the new inverter. that would seem a much more likely explanation than having other components suddenly failing.
February 21st, 2011, 06:40 AM
kleefarr

Agreed, that would be the simplest solution, but the display was not showing when I got the laptop so wouldn't know if the same problems were occurring or not.
When I replaced the LCD inverter the display came back, so I assumed that had been the problem and may well be one of the problems. finding out what the other problem is the task.

Can I rule out the backlight? All though there is slight flickering when brightness turned down, there is no discolouration that you would normally see with backlight problems.

am stripping down the screen completely and double checking wires.
February 21st, 2011, 05:31 PM
slgrieb

Quote:

Originally Posted by kleefarr

Agreed, that would be the simplest solution, but the display was not showing when I got the laptop so wouldn't know if the same problems were occurring or not..

Is this a machine you bought for yourself, or is it in for repair? Asking the customer about problems can be a useful diagnostic tool. I still think the inverter is at fault. A bad backlight is going to display problems when it starts, but not the intermittent glitches you're seeing. I don't think there is enough flickering, etc. going on.
February 22nd, 2011, 05:31 AM
kleefarr

In for repair. I have had this laptop in for repair before. I actually asked the customer about the new damage that was showing on the laptop. Knew it had been dropped at some point and that was confirmed.

It's working now anyway. :rolleyes:

Not exactly sure what the problem was, but I stripped it down, including wires and reseated all the connections. Was running fine all day yesterday and has now been returned to the customer. He said his daughter watches films in bed on it and then goes to sleep. Of course the laptop then ends up on the floor more often than not. :eek:
I told him she was lucky that nothing more serious had happened to it. :rolleyes:

I'll get it back again at some point I guess.

Thanks for the input and sorry for wasting your time. :(
February 22nd, 2011, 11:09 AM
Kodiak

What I do in these cases is I have an old backlight that works and I plug it in to eliminate the screen as the problem. If you have a broken screen you can pull the backlight out of it, that's if it is good.
February 24th, 2011, 05:47 PM
slgrieb

Quote:

Originally Posted by kleefarr

In for repair. I have had this laptop in for repair before. I actually asked the customer about the new damage that was showing on the laptop. Knew it had been dropped at some point and that was confirmed.

It's working now anyway. :rolleyes:

Not exactly sure what the problem was, but I stripped it down, including wires and reseated all the connections. Was running fine all day yesterday and has now been returned to the customer. He said his daughter watches films in bed on it and then goes to sleep. Of course the laptop then ends up on the floor more often than not. :eek:
I told him she was lucky that nothing more serious had happened to it. :rolleyes:

I'll get it back again at some point I guess.

Thanks for the input and sorry for wasting your time. :(

No apology needed. I think we're all professionals on this bus, and who hasn't experienced a situation where re-seating cables hasn't fixed some oddball problems?