Drop Detector Failure.
Try the following:
1. Check that the Drop Detector Cable is NOT broken or damaged.
2. Check that the Drop Detector cable is correctly connected to the Service Station Cable.
3. Remove the Drop Detector and make sure that there are no obstacles inside which are blocking the sensor.
4. Replace the Drop Detector Assembly.
5. If the System Error Code continues, replace the Main PCA.
Only replace one component at a time and check if the error has gone before replacing another component. Using this procedure you will be able to determine exactly which component failed.