Citroen C8 gear shift indicator problem

Whoa, that sounds rough! A blank gear indicator and all those shifting problems definitely point to something electronic going haywire. When you say 'error code,' do you remember what it was? Knowing the exact code could really narrow things down. It sounds like it is not registering correctly when you change gear. Have you checked the shift knob itself for any obvious damage or loose connections? Is it difficult to move?

Thanks for the quick reply! I didn't write down the code, stupidly. I checked the shift knob, and it seems okay – moves smoothly enough, no obvious breaks. What sort of electrical issue could cause all this?

Okay, without the code, it's tough to say for sure. These things have control units, which is a mini-computer that runs the automatic transmission. And the symptoms you describe sound unfortunately like a control unit issue. Given it's affecting the gear selection and the display, it's very likely that's where the fault lies. I hate to say it, but this usually means a trip to a workshop is unavoidable – they have the proper diagnostic tools.

Yeah, I figured as much. Thanks for confirming my fears! Took it to a local garage. They said the control unit is fried, exactly as you thought. Quoted me around 1000€ for the repair. Ouch! But at least I know what the problem is. Thanks again for your help.