Dishwasher
E5
The E5 error code on a Bosch dishwasher signals a water temperature fault — specifically that the water is overheating or that the temperature sensor (NTC thermistor) is detecting a reading outside the normal range. It’s a moderately serious fault that will stop your dishwasher mid-cycle, but in many cases it’s fixable without a call-out.
What does this error mean?
Your Bosch dishwasher continuously monitors water temperature using an NTC thermistor (a small temperature sensor). The E5 code triggers when the control board receives a temperature reading that is too high — typically above 75–85°C — or an implausible spike that suggests the sensor itself has failed. In practice, this usually means either the heating element is stuck on, the thermistor is faulty, or the control board is misreading the sensor signal. The machine halts as a safety precaution to prevent damage to your crockery, the internal components, and the appliance itself.
Est. repair cost
£10–£25 DIY thermistor replacement; £80–£160 professional repair (element or thermistor); £180–£280 if PCB replacement is needed
🔍 Likely causes
🛠️ Step-by-step fix
Reset the dishwasher: Turn it off at the mains, wait 5 minutes, then power it back on. A one-off software glitch can occasionally trigger E5, and a hard reset clears it. Run a short cycle to see if the error returns.
Check the water supply: Make sure the inlet tap (usually under the sink) is fully open and the inlet hose isn’t kinked. Low water flow means the element heats too little water, risking a temperature spike.
Run a descale cycle: If you live in a hard-water area, fill the detergent dispenser with a dishwasher descaler (e.g. Finish Dishwasher Cleaner) and run a hot empty cycle. Heavy limescale on the element is a real contributor to overheating faults.
Inspect the thermistor (if comfortable doing so): Pull out the lower basket and remove the lower spray arm. The NTC thermistor is a small probe clipped to the sump area at the base of the tub. Check it for visible damage or corrosion. A functioning NTC thermistor on a Bosch dishwasher typically reads around 6,000–10,000 ohms at room temperature — test with a multimeter if you have one. A wildly different reading (or open circuit) confirms it needs replacing. Replacement thermistors cost £10–£25 and clip in without tools.
Check the heating element for continuity: With the dishwasher unplugged, access the element terminals (usually at the rear or beneath the machine after removing the kickplate). Use a multimeter on resistance mode — a healthy Bosch element reads roughly 20–30 ohms. An open circuit (OL/infinite) means the element has failed and needs replacing. This is a DIY-accessible job but requires confidence working around electrical components — if in doubt, stop here and call a professional.
If the error persists after steps 1–5, the control board (PCB) is the likely culprit. Do not attempt to repair or replace the PCB yourself — this requires a qualified appliance engineer.
📞 When to call a professional
If the E5 error returns after a reset, a descale, and a thermistor replacement, you are most likely dealing with a failed heating element or faulty PCB — both of which require a qualified appliance engineer for safe diagnosis and repair. When you call, tell the engineer: ‘My Bosch dishwasher is showing an E5 error code — I believe it’s a temperature/overheating fault, and I’ve already reset it and checked the thermistor.’ This will save diagnostic time and money.
⚖️ Repair or replace?
A professional repair for an E5 fault — covering call-out, thermistor or element replacement — typically costs £80–£160 in the UK. If the PCB needs replacing, costs can rise to £180–£280 including parts and labour, at which point repair may not be economical. As a general rule, if your Bosch dishwasher is over 8 years old and the repair quote exceeds £150, it’s worth comparing against a new mid-range model (£350–£550), especially given improved energy efficiency on newer machines.