Supply water temperature sensor is shorted. '0' Ohm
1. Disconnect wire harness from high temperature supply switch. Measure resistance across terminals 2 and 4. Does temperature fall within ranges shown in chart?
Yes: Replace high temperarture supply switch
No: -> 2
2. Disconnect J5 from control module. Continuity between J5-11 and switch2? Continuity between J5-3 and switch 4?
Yes: Replace control module
No: Replace wires