Tighten LED bar on 27" Display to quiet down random pops and clicks

[howardc64]

Quite a few screws was several turns loose. Tighten them and quieted it down. Quite a surgery of course and easy to get dust in btw LCD and diffuser requiring 2nd disassembly to clean off (can't see result of first pass cleaning until LCD is on again). 2-3 hours even with experience (I've done like 20 of these, mostly Thunderbolt Displays with blacking out backlight)

While there, I reflowed the LED bar connector solder points as preventive for blacking out backlight problem. Occurs mostly on 27" Thunderbolt Displays (same LG 27" LCD+backlight panel) but have seen it on 1 A1312 iMac.

Apple Thunderbolt Display Black Blanking Out Repair

Thunderbolt Display uses an LG edge LED lit LCD Display (also 09-11 27" iMacs and 27" Cinema Displays). The LEDs are on the bottom edge of the...

www.ifixit.com

 

[FreakinEurekan]

I know some models of the 27” iMac had a spring issue where it’d fall forward after a while. Does the TBD do that? If so it might be worth the time to replace the spring while it’s apart.

 

[howardc64]

I know some models of the 27” iMac had a spring issue where it’d fall forward after a while. Does the TBD do that? If so it might be worth the time to replace the spring while it’s apart.

Only seen that on 1x used A1312 out of ~20 I've seen. None on the ~20 used TBD. A1312 are heavier than TBD and if people lay it on its back will exert a lot of force on that hinge. I put a pillow/rolled towel under these when on its back.

 

[PaulD-UK]

Some iMac 27” 2012/13 models had the problem (Apple acknowledged this). Their hinge is not the same as the TBD.