Hobart lx 40 - problem D 1

Does it show a wrench icon and P1?
error codes are p 1to 3 for probe errors, or E1 to 7 for error codes.
P1 is the probe on the wash tank. It's a thermistor with two black wires to a white connector. There is another on the booster front (P2) and a 3rd on the rear airgap, (p3). You could try exchanging 1 and 3 to see if the fault changes too. You have to drain the booster to swap P2. If it can't determine the wash tank temp, it won't know to control the heat and shows the error.