Loading ...Q
I am the proud owner of a 1994 740IL. This car presently has 195,000 miles on it. My wife and I have noticed lately that the ride on this car is extremely rough. We had new shocks (“00″ type) installed about 60,000 miles ago and are wondering if they have gone bad. I was reading my Bentley manual for this car and ran into this note that stated if the power is off for any point of time that the EDC III system goes into a firm setting. We did have an incident about a year ago where we parked the car at an airport and left the lights on. When we returned the car would not start and we had to have it jump started. Would this incident have caused the EDC III system to go in the firm mode? If so, how would one reset it back to the soft mode? The Bentley manual gives no instructions on this except for taking it to a certified expert.
A
The EDC (Electronic Damping Control) system takes inputs from sensors on the suspension (that detect suspension travel), vehicle speed and a steering angle sensor. These inputs go to the EDC control unit, which then controls the shock valving between soft, medium and firm. When the selector switch is in the Comfort setting, the system runs with soft as the priority, but will go to medium or firm if the sensor inputs warrant this. In the Sport setting, the system operates between medium and firm, with medium as the priority until the sensor input causes a change to be made by the control unit. We have not heard of a condition of going to firm if the power is interrupted, but then staying firm when the power is restored. If your system is constantly in the firm setting, you may have a fault in the control module or one of the sensors. Alternately, there may be no power to the system. Check the system power fuses, #12 and #45, as a start. If the fuses are OK, a BMW dealer should be able to plug into the system to check for internal fault codes.
