matt66604

I've recently encountered the C3 electric power steering. After trying to research some stuff about it and not finding anything of use at all.. I thought id post something up which may be of interest. initially the fault I had with the car was steering pulling violently to the right. after using my launch easydiag tool, there was a stored fault relating to faulty ecu (plus I couldn't read live data, too many comm errors to continue) so £25 later and a replacement ecu from ebay, I could now read the live fault data. No faults were stored with the system. I checked the readout from torque sensor and it was constantly at least +4NM of right hand steering force. after visual inspection of the rack I encountered the "apparently common" crack in the rack housing, after another £30 on ebay I got a replacement rack complete. obviously I obtained ecu and rack with exact part numbers to ensure compatibility. new rack fitted, track rods complete with ends swapped over to ensure geometry is the same. tried it out and it was definitely better but still not spot on.. after stripping the old rack for a nosey as I was intrigued, I found the crack in the rack allows moisture to ingress into the motor and torque sensor assembly causing the faults. I found there is a small plate held on with 2x T20 screws on the torque sensor housing. Under this plate is a electronic board with a small potentiometer inset. after playing with this I found this is used to zero your electric steering. with reading out the live data from the torque sensor, I found it was definitely out by 1.7 NM + to the right... I adjusted the potentiometer anticlockwise to the zero position to counter the positive right hand force. and hey presto. The car drives like brand new again. simple little potentiometer which turns left and right to adjust respectively. so I hope anyone who is having this problem with the steering pulling on their Citroen will see this and hopefully this will help you out... when putting the small plate and seal back on best to use a small amount of grease around the seal area to help stop aluminum corrosion and water ingress further down the road..