Bosch Refrigerator E2, E3 Ice Maker and Sensor Error Codes
Quick Answer
Bosch refrigerators use fewer error codes than most brands because Bosch designs for simplicity. The main codes are E2 (ice maker temperature sensor fault) and E3 (freezer temperature sensor fault).
When E2 or E3 shows up, your fridge is basically flying blind through its cooling cycles. I've seen a ton of these where the sensor just got buried in frost and a good defrost fixed everything without spending a dime. But ignore it long enough and your compressor starts overworking itself trying to hit a temp it can't actually read. Food spoils. Ice maker quits. Worth dealing with today, not next week.
BoschRefrigerator
About These Bosch Refrigerator Error Codes
OK so Bosch keeps their error code system dead simple, which I honestly appreciate. You won't get buried in 40 cryptic codes like some brands do. If E2 or E3 shows up, it's almost always a real hardware issue rather than a software hiccup. My first move is always to check for frost buildup around the sensor probe before I even grab my multimeter. Nine times out of ten, that's it right there.
Most Common Error Codes
Ice maker sensor fault (E2) - frost buildup most common45%
Freezer temperature sensor fault (E3)30%
Power surge corrupting control board15%
Sensor connector corroded from moisture10%
Symptoms You May Notice
E2 or E3 flashing on the display, sometimes with an audible beep every few minutes that'll drive you absolutely crazy.
Ice maker completely stopped making ice, or it's producing those weird small hollow cubes because the temperature data is wrong.
Freezer contents are inconsistent: stuff that should be rock solid feels slushy, or you're seeing way more frost than usual on everything.
Compressor won't shut off. Just runs and runs constantly because the board can't confirm the target temp has been reached.
There's a solid sheet of frost coating the back wall of the freezer compartment, which is usually what caused the sensor fault in the first place.
Tools Required for Diagnosis
Phillips #2 screwdriverSmall flathead screwdriver (for connector release tabs)Digital multimeter with ohms settingFlashlight or headlampHair dryer (low heat, for defrosting sensor area)Electrical contact cleanerCotton swabs
How to Identify Your Error Code
ComponentComponent Under Test
Expected Range8000–12000 ohms
ConditionIf Open (OL) or infinite, replace component.
Replacement Parts
If your diagnostic testing proves the component has failed, you will need a replacement. We recommend OEM parts over aftermarket for water-handling components.
Part Name
OEM Number
Estimated Price
Bosch Ice Maker SensorModel-specific · $20–$40
Model-specific
$20 – $40
Bosch Freezer SensorModel-specific · $20–$40
Model-specific
$20 – $40
Frequently Asked Questions
Does Bosch have a diagnostic mode for refrigerators?
You won't find a secret button combo on the front panel like you do with Whirlpool or GE. Bosch uses a proprietary service port, usually on the main control board housing, and techs plug a specialized tool into that port to read live sensor data. For homeowners, your best bet is testing the sensors directly with a multimeter at the board connectors to see if they're reading in the correct ohm range. That tells you everything you actually need to know anyway.
Are Bosch fridge error codes the same as Bosch dishwasher codes?
Absolutely not, and don't make that mistake. Bosch uses completely different logic for their refrigeration line versus their dishwashers. An E15 on a dishwasher is a flood sensor trip. On a fridge it means something totally different. Never use a dishwasher service manual to troubleshoot your fridge, or you'll end up replacing parts that aren't even broken. Always make sure you're looking at refrigerator-specific documentation for your exact model number.
Where do I buy Bosch fridge parts?
Get your full model number AND the FD number (Factory Date) from the sticker inside the fridge door frame before you order anything. Bosch makes mid-production changes to their sensor specs pretty regularly, and an aftermarket thermistor with the wrong resistance curve will cause your food to freeze or spoil because the board gets garbage data. Buy OEM Bosch sensors. Yeah they cost a little more than the $8 knockoffs on Amazon, but I've had to go back to fix cheap sensor installs more times than I can count.
How much does it cost to fix E2 or E3 on a Bosch fridge?
If it's just frost buildup around the sensor, literally $0. Defrost it and you're done. A replacement NTC thermistor is usually $15-30 for the part, and it's a pretty easy DIY swap if you're comfortable with basic appliance work. Where it gets expensive is if the fault is actually on the control board, which can run $150-300 for the part plus labor if you hire someone. Always confirm the sensor is bad with a multimeter reading before you spend that kind of money on a board.
Can I still use the fridge while E2 or E3 is showing?
Short answer, yeah, probably for a day or two. The fridge will still try to cool, but without accurate sensor data the cooling cycles won't be right and your temps will swing more than normal. I wouldn't trust it longer than that. If you need a few days to get parts, keep a fridge thermometer in both compartments and check morning and night. Don't let it sit for weeks though, because the compressor is running blind and that's how you end up with a much more expensive repair down the road.
How long does a thermistor replacement actually take?
Honestly? If you've done it once before, maybe 30 minutes. First time, budget an hour. The actual sensor swap is dead simple once you've got the evaporator cover off. The annoying part is pulling all your food out, removing the shelves, taking off the back panel. The repair itself is like four screws and a connector. I walked a homeowner through replacing her E3 sensor over text last week and she got it done on her first try. Pretty much anyone who's comfortable with basic DIY can handle this one.