A while back, we installed a Sony radio in our Xsara Picasso which promptly disabled the trip computer, is there a way to get the computer back while keeping the new radio??
I haven't installed the control stalk adapter as I can't work out where it plugs in so don't know if that would fix it!?!

I've found the answer!!! After 2 years of searching: Turn car off and wait 5 mins inside car with doors closed. Push the left front seat so it's fairly central, push down two clips at back of seat base and tip seat forward to get access to battery. Take off battery cover. Disconnect -ve (green) terminal ONLY. Wait 5 mins. Reconnect everything. Trip computer worked! Someone answer with this please so the answer is here!!