E18
Bosch Refrigerator
Severity: ModerateWhat Does This Error Mean?
Error E18 means the temperature sensor inside the ice maker compartment has failed or lost contact. The control board cannot confirm the correct temperature for ice production. The ice maker will stop producing ice until the sensor fault is resolved.
Affected Models
- Bosch Serie 6 KGN86AIDR
- Bosch Serie 4 KGN39VXBT
- Bosch French Door B36CT80SNS
- Bosch Counter-Depth B11CB81SSS
- Bosch Serie 8 KGN86AIDP
Common Causes
- Ice maker compartment NTC sensor open-circuited due to age or damage
- Ice buildup around the sensor causing it to read incorrect temperatures
- Wiring connector between sensor and control board has come loose
- Moisture intrusion into the sensor housing causing a short circuit
- Control board channel for ice maker sensor has failed
How to Fix It
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Unplug the refrigerator and locate the ice maker compartment sensor.
The ice maker sensor is typically mounted on or near the ice maker unit inside the freezer — consult the service manual for your exact model.
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Manually defrost any ice buildup around the sensor using a hair dryer on low heat.
Heavy ice accumulation can physically trap or distort the sensor, causing false readings — clearing it first rules out a simple fix.
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Disconnect the sensor connector and test resistance with a multimeter.
A functioning NTC sensor reads 5–10 kΩ at room temperature — an open or shorted reading confirms sensor failure.
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Inspect the wiring harness from the sensor to the board for any damage, pinching, or moisture.
Ice makers are in a wet environment — wiring corrosion is a common cause of intermittent sensor faults.
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Replace the ice maker compartment sensor with a genuine Bosch OEM replacement part.
Match the part number to your refrigerator model — ice maker sensors vary across Serie 4, 6, and 8 models.
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Reconnect power and wait 60 minutes to confirm the error has cleared and ice production has resumed.
The first ice production cycle after repair can take 30–90 minutes — this is normal.
When to Call a Professional
Call a technician if replacing the ice maker sensor does not clear E18. Repairs involving the ice maker assembly or control board typically cost $150–$350. If your refrigerator does not have an ice maker, this code may indicate a wiring issue — do not ignore it.
Frequently Asked Questions
Will E18 stop all freezer cooling or just the ice maker?
E18 only affects the ice maker compartment sensor — the main freezer cooling will continue. Your food will stay frozen, but the ice maker will stop producing ice. Fix the sensor to restore ice production.
Can I bypass the ice maker sensor to use the freezer normally?
The freezer will continue working normally even with E18 active. You cannot bypass the sensor to restore ice production safely. Replace the faulty sensor — it is a low-cost repair that restores full function.
How long does ice maker sensor replacement take?
For an experienced DIYer, the replacement takes 30–60 minutes. The sensor is accessible after removing the ice maker unit from the freezer compartment. A technician will typically complete the job in under an hour.