LG Dishwasher LDS5811ST 1E error code

Question

HiI have an LG dishwasher that keeps giving an 1E error code. The code means water inlet trouble and recommends the following. Check clogging of water inlet hose(or hose twist or freezing)Check if it's suspension of water supplyAfter following the troubleshooting guide and checking to see if the inlet valve is operational. The LG parts supplier said that it may be the control board timer and not the inlet valve.How do i diagnose if it is the control board and not the inlet valve? where can I get a diagram to help replace the control board? ThanksCarl