Technical Uconnect dark but the touchscreen and audio are all working ok. Any ideas ?

[buggi]

Hi all,

we have a 2021 mild hybrid with 7" touchscreen. Wife said the display would flicker and then go dark but everything (touchsceen, audio , car play etc seem to be working ok.

It looks like theres something working on the backlight as the display changes to dark grey (is the backlight working but no signal to it ?)

Can bus seems to be working ok as the speedo display is mirroring the uconnect and all controls working.

I've stripped it down to check for damaged /loose ribbon cables etc but nothing obvious. (and phew everything else still works or i'd have been in big trouble with the mrs)

When powered up, the unit gets warm and I noticed the 12V fan isn't running with no voltage to it.

I saw a temperature sensor mentioned somewhere ? has anyone an idea where this is (the uconnect may be thinking its overheating?)

So I'm unsure whether its the backlight faulty or the signal to the display ? I can put a scope onto the display signals but not sure which cable is which .

So i could swap out the display only (expensive) or the whole unit (extremely expensive ) - but might just be a faulty ntc or poor connections.
Any ideas much appreciated (promise to share any brownies points if I can fix it).

TIA

 

[ZaphodB]

Backlight's probably an electroluminescent panel, and it is not uncommon (generally) for them to fail and go a bit flakey beforehand.

Not usually replaceable, but depends on the construction/manufacturer.
I can't see why there'd be an NTC , but there could be an ambient light sensor.

Show me pics

 

[buggi]

Thanks. I'll get some PCB photos later (I wish i'd taken some at the weekend. display model is VP2RFP. So it could possibly be the EL driver? If I can find it on the PCB I'll put a scope on the output . I guess I'm looking for ~12V square wave or similar to driver the EL panel.

 

[ZaphodB]

Anything's possible but generally (out of the fiat world if you get me) not usually the driver that would fail, but the actual EL panel.

 

[buggi]

Thanks. the panels are available off ebay and a lot less of a nightmare than changing the whole assembly .