This is not a fault I can just talk you through as it needs first all the wiring checking and continuty checks then pin signal checking to and from various control modules it will need to go to Citroen dealer or an auto electrical specialist to resolve this problem. I told you some basic checks you can do above.
Citroen C4 Picasso full automatic AM6 C4 Picasso epb Hi got a 2014 C4 Picasso diesel auto and it's been 2008 Grand Picasso - Faulty Gearbox - Electrical fault
I have a 2003 citroen xsara 2-0 hdi auto 5 door saloon it has an anoying gear box fault after starting the car from cold and runnig it for about ten minuts the sport & snow lights come on and the car … read moreThanks - the RAC had also theorised that the ESP alert and the other faults might be related to the injector fault, hence clearing the fault list and re-doing the diagnostics. I've had it recovered to the garage I bought it from - much to their chagrin (as I didn't buy a warranty), but 10 days and only 300ish miles after buying it, clearly I am FmLxS.