The Story goes:
One morning my Xsara wouldn't start... It's a year 2000 1.6i petrol with AL4 transmission. The sport and snow lights were flashing in the instrument panel indicating that there's a problem with the transmission ECU. The Mechanic at Citroen couldn't connect his computer to the transmition ECU and it was dead! He then put a new AL4 ECU and sent me on my way. A few days after the problem reacurred, but this time, after a minute it was gone and the car started normaly. I went back to the shop where they connected the diagnostics computer and found no faults at all. They then proceeded to check the cables and connectors between the ECUs for damage. They removed the battery and lo and behold ? a pool of acid and corrosion all over under battery area and on top of the cables, eating away the insulation and getting into the connectors. It's a miracle the car ran at all. The funny thing is that the top of the battery looked clean and tide with no noticeable corrosion. He thoroughly cleaned and covered the cables with a new coat of insulation and fitted a new battery. After a few days the same problem is back again, but not regulary!!! sometimes the car starts normally, somtimes it doesn't. Does anybody have experience with this fenomenon? I don't think the dealer really knows this problem and how to fix it (more importantly - what causes it) because the ECU doesn't show any faults.