My 2006 Citroen C4 diesel (120,000 km, often serviced, great ailment) has been indicating by warning lights on its screen faults with Anti-Air pollution and ESP/ABS systems. A Citroen specialist I've used for years (not a dealer) has told me that it's a communications problem related to the vehicle's computer. https://kajakklubbenase95048.weblogco.com/33538691/not-known-facts-about-sell-my-car