My head unit (central screen) is completely black and not responding at all. The screen between dials on instrument panel is however, fine.

Have I bricked the head unit, or does it just need a re-code?

I did take it out, as needed to clean the space behind it. Not wanting it to dangle, I did disconnect it.

Recently changed the battery, but that was weeks ago, and didn't cause any problems.

I've found that the cabin filter only has foam on two sides, not four, so dirt was taking the easy route instead of going *through* the filter 🙄

I have ODBII, or would i need VCDS?

Update: OK there seems to be a bit of life left 🤒

• buttons have their illumination at night

• power button causes the backlight to glow faintly (screen still black)

• little later, the animated logo displays ...

• ... then shuts down completely

• will repeat with further presses

I'll give it a clean with my can of air, but further information or suggestions greatly appreciated.

PS. dirt seems to be coming from a defective exhaust gas temperature sensor. I can get a spanner on it (i.6 has a bit of elbow room) but it isn't budging -- Is it easier to replace that bit of exhaust pipe?

You’re stuck in a boot loop. Remove the unit, set it up on a workbench, and establish a UART connection. Check if the boot flash is still functional. If it is, force the device into emergency mode and perform a firmware reinstallation.

Thanks Cairus,

Sounds hopeful, but I have a few questions;

• have I corrupted some part of the boot process?

• Is this similar to Amundsen MiB1 Firmware Update process, but off the car?

• do i need a UART - USB adapter like this little blue board to connect to a laptop? or VCDS? -- I assume the former, otherwise it wouldn't need a workbench. Also I assume the workbench needs a 12V supply

• do I need specific software or will a terminal CLI do?

• does the unit have the firmware for reinstallation, like a factory reset or do I need a file as with the Firmware Update process? I notice it mentions creating a Mirror Copy (maybe this is its purpose?) (Intending to update to 0490 when it's working)

Hope these aren't too stupid ...

Off to look though my collection of manuals, but I'm not sure they cover this sort of thing.

BTW could we do with a write up on this?