Why did the reverse gear suddenly stop working, but it was fine an hour later, on a Trailblazer?

I've upgraded my 2009 Scirocco with the 187b head unit, but the reverse camera doesn't switch the screen when reversing, although the radar works fine. Interestingly, the reverse camera works normally when the car is off, but not when the engine is running. I've already replaced the head unit and the reverse camera, but the issue persists. Any experts out there who can help?

Why did the reverse gear suddenly stop working, but it was fine an hour later, on a Trailblazer?

Why did the Haima S5 suddenly stall while driving?

Why did the engine warning light turn on and the D gear light keep flashing after driving my 2014 Honda City automatic on the highway for three hours?

Why is this Bluetooth always showing in black and not working? Other functions are fine.

Are there any owners of the 2018 model using the original car navigation? I want to ask if the power and mute buttons on the left side of your original car navigation work. Why did mine stop working? The volume button on the right side works.

Have you ever experienced the charging process suddenly stopping halfway? I've encountered this several times recently. Sometimes it stops just after charging a few kilowatt-hours, other times it stops at 80% or even at 90%... I'm not sure what's causing it.

Why is it difficult to engage reverse gear in a 2021 manual transmission?

Gear position not displayed, a constant line, and the reverse radar is not working.

What kind of bulbs did you buy to replace the ones that stopped working on your 2018 model?