Bosch Dishwasher Service Test Result 8: Temperature Sensor

What 8 means

When an older Bosch dishwasher answers the service test with an 8, the NTC temperature sensor is the culprit. The full-text version of the same manual calls it short-circuited or open-circuited, the two usual ways such a sensor dies. The machine then cannot judge water temperature, and heat and timing both go unreliable: cycles may run long, finish early, or wash in water that never gets hot.

Common causes of 8

Sensor reading open circuit
Sensor reading shorted
Sensor lead or plug failed

✓ One safe check you can try

1. Leave the machine closed; checking an NTC means measuring resistance with the power off. 2. Watch the next few cycles. 3. Note whether they run long, end early or wash in lukewarm water. 4. Report that to us when you call; it helps us arrive prepared.

! Why to stop there

Sensors are tested with a meter on a dead machine.
A connector problem looks identical to a failed sensor.
A wrong temperature reading can make the heater run longer than intended.

Opening a panel yourself does not automatically cancel a manufacturer warranty, but it can cause accidental damage, and some manufacturers set their own service conditions. Check your warranty terms, or ask us, before deciding.

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Other Dishwasher codes

E:30Bosch Dishwasher E:30, voltage too high and the machine shut down E:31Water in the zeolite container - Bosch Dishwasher E:31 FBosch Dishwasher F on an older display (water filling) 2HBosch Dishwasher 2H: Long Cycle Warning on Older Displays 1Bosch Dishwasher Service Test Result 1: Aqua Sensor 2Bosch Dishwasher Service Test Result 2: Heating Group 4Bosch Dishwasher Service Test Result 4: Water Filling 16Bosch Dishwasher Service Test Result 16: Spray Diverter

88 questions

What does open or shorted mean for a sensor?

Open means the circuit is broken, so the reading is off the scale; shorted means it reads zero. Either way the machine cannot tell the water temperature.

Is a temperature sensor an expensive repair?

It is usually a modest part. We measure first, then quote, so the written price reflects only what is actually needed to get the machine heating properly.

Can bad readings damage the dishwasher?

They can lead to heating longer than needed or washing in cold water. It is worth fixing soon, but nothing dangerous happens right away, so there is time to book a visit.