Error in Scan-axis Encoder quadrature.
Try the following:
1. Check that the Encoder Strip is NOT broken or damaged.
2. Replace the Encoder Strip.
3. Replace the Carriage Assembly.
4. If the 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.