Bosch Dishwasher Error Code Test

The Test error code on a Bosch dishwasher indicates that no heating is occurring during the wash cycle. The machine has detected that water temperature is not rising as expected, which points to a faulty heating element, insufficient supply voltage, or excessive limescale on the element. The dishwasher will not complete a normal wash cycle effectively until the underlying cause is corrected.

Running the dishwasher with an active heating fault means the water will not reach proper cleaning and sanitization temperatures, so dishes may not be hygienically clean. There is also a risk of the faulty element causing further electrical issues if it is shorted or damaged. It is best to resolve the fault before continuing regular use.

A reset may temporarily clear the fault code from the display, but it will not resolve the underlying problem. If the heating element is faulty, the voltage is inadequate, or scale is present, the error will return as soon as the machine attempts to heat the water again. A proper diagnosis and repair of the root cause is required to permanently clear the fault.

Start by disconnecting the heating element and measuring its resistance with a multimeter. A healthy element will read between 23.2 and 29.4 ohms. If the reading is outside that range, the element needs to be replaced. If resistance is correct, check for limescale buildup on the element and verify that proper voltage is reaching the heater terminals during operation.

If only descaling is needed, the cost is minimal, typically just the price of a descaling product. Replacing a heating element generally costs between $80 and $200 depending on parts and labor in your area. If the control board is the culprit, repair costs can range from $150 to $400 or more.