One morning my Xsara wouldn't start... It's a year 2000 1.6i petrol with AL4 transmission. The two transmission indicator lights (s) & (*) were blinking in the instrument panel indicating that there's a problem with the transmission ECU.
The mechanic at Citroen tried to establish communication with the transmission ECU but to no avail. the engine ECU responded well and reported no faults but additional tries to connect to the transmission ECU failed. The mechanic deduced that the ECU must be replaced and couldn't really tell me what happened other then the fact that it's dead! I was concerned though of what happened to the ECU and how to prevent it from happening again. I don't know if the death of the ECU was the cause of the problem or the outcome of another problem that I'm not aware of - in which case the problem should reoccur.
The new ECU worked great but, alas, after two weeks it happened again! the gear lights were blinking and the car wouldn’t start... fortunately this was temporarily and a minute later I tried again and all seemed well with no sign of a fault.
This time the ECU didn't die, the mechanic established connection with it with no faults noted. He then proceeded to check the cables and connectors between the ECUs for damage. He removed the battery and lo and behold – a pool of acid and corrosion all over under battery area and on top of the cables array, eating out 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. (he charged me for the battery and the work but I knocked the work down because he really had to do that the first time around! – don’t let them rob you!)
The car is running perfectly for now, I only hope there’s no corrosion damage to the cables or they’ll have to be replaced too.
I hope this story will benefit someone.
What’s your take on this??
Oren.
Xsara transmission ECU story
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