Bosch dishwashers draw hot water from the household tank and use a heating element inside the appliance to sustain water temperature. The element also activates during the powered dry cycle to dry dishes faster and reduce spotting. If the water isn't heating up in the Bosch, try troubleshooting the dishwasher for common problems that you may be able to fix yourself without calling a repair technician. Follow all safety precautions when troubleshooting this high-voltage appliance.
Unscrew the curved metal plate on the side of the household hot water tank, using a screwdriver. The water temperature control is underneath the plate.
Dial the temperature control to 120 degrees Fahrenheit and replace the cover plate. This is the optimal temperature for heating water to disslove detergent in the Bosch dishwasher. Any cooler and the water cannot get dishes clean. Any hotter and you run the risk of scalding when running water in the sink or shower.
Shut off the electricity to the Bosch at the household circuit breaker.
Open the dishwasher door and pull out the bottom rack to check for any obvious signs of damage on the heating element inside the bottom. Cracks, chips and scorching are all signs that the element is defective.
Take out the screws in the sides of the bottom plate on the front of the Bosch. Pull off the plate to locate the two points where the heating element connects to the wiring under the appliance.
Slide off the two wires at the connectors on the heating element.
Set the multimeter to read for ohms and touch the two wands on the end of the device to the two heating element terminals. If the meter registers zero or the display fluctuates constantly, the element is bad and the water will not heat properly in the Bosch until the element is replaced.