This error indicates that the water temperature does not get sufficiently hot. Either the relay in the control board or the pump/water heater are likely the problem. In this model, the control board is located on the right side of the washer. It is easily accessible once the unit is pulled out. An inspection of the board showed no visible damage. I was pleased to notice that Bosch uses high quality components in the board. No Chinese cheap parts. Several YouTube videos show how to troubleshoot the pump without removing it. The heater element is part of the pump housing, heating the water as it passes through it. Simply doing a continuity check on the heater connector is all that is needed to know that the pump is defective.
To get access to the pump, the dishwasher must be removed completely, disconnecting all water ports and electrical supply. Lay the unit on its back. Make sure you have a Torx set. I spent some time figuring out how to remove the plastic base. Not overly complicated if you are mechanically adept. I found out that there is a leak sensor mounted in the plastic base. Good to know. The pump is held in place by a couple of screws and a crimped hose clamp. The replacement pump was identical to the original and it came with a hose clamp that requires a crimping tool. I used instead an adjustable hose clamp. I reassembled the unit, set it upright, mounted temporarily on wood blocks, reconnected everything and ran a test cycle. The washer ran perfectly.