Bosch Refrigerator Error E25 — What It Means & How to Fix It

What Does This Error Mean?

Error E25 means the main control board and the display board have lost communication with each other. The refrigerator may continue cooling but settings cannot be changed and the display may be blank or frozen. This is usually caused by a wiring fault or a failed board, and requires diagnosis to resolve.

Affected Models

Bosch Serie 6 KGN86AIDR
Bosch Serie 4 KGN39VXBT
Bosch French Door B36CT80SNS
Bosch Counter-Depth B11CB81SSS
Bosch Serie 8 KGN86AIDP

Common Causes

Communication wiring harness between the main board and display board damaged or disconnected
Main control board has failed and can no longer send or receive data signals
Display board has failed internally and is not responding to the main board
Power surge damaged one or both boards causing communication interface failure
Loose or corroded connector on either the main board or display board communication port

How to Fix It

Unplug the refrigerator for 5 minutes and plug it back in to attempt a full control system reset.

A complete power cycle clears temporary communication errors caused by software glitches or brief power fluctuations.
If E25 returns after the power cycle, access the main control board (usually at the rear bottom of the unit).

Consult your model service manual for the exact location — on some models the board is inside the unit behind a panel.
Inspect the communication wiring harness running between the control board and the display panel.

Look for any chafing, pinching in the door hinge area, or connectors that have pulled partially loose.
Reseat all wiring connectors on both the main board and display board by pressing them firmly until they click.

Vibration over years of use can cause connectors to work loose gradually — reseating them often clears intermittent E25 errors.
Test the communication harness for continuity between the main board and display board connectors.

Any wire in the harness that reads open (OL) indicates a broken wire — the harness must be replaced.
If the harness is intact, replace the main control board or display board as directed by your technician's diagnosis.

Board replacement typically requires reprogramming — a Bosch-certified technician should complete this step.

When to Call a Professional

Call a technician if the wiring harness is intact but E25 persists after a power cycle. Control board replacement costs $150–$400 depending on which board has failed. Do not attempt to solder or repair circuit boards yourself — replace the failed board with a Bosch OEM unit.

Frequently Asked Questions

Will my Bosch refrigerator still keep food cold while E25 is showing?

In most cases yes — the compressor and fans continue to run on their last known settings. However, you cannot change temperature settings or monitor temperatures via the display. Arrange a repair promptly as a fully failed control board can eventually stop all cooling.

Can a power surge cause E25 on a Bosch refrigerator?

Yes — voltage spikes are one of the most common causes of communication board failures. If E25 appeared immediately after a power outage or surge, one or both boards may have been damaged. A surge protector or whole-home surge suppressor helps prevent this type of damage.

Is E25 a DIY repair or do I need a technician?

Checking the wiring harness and reseating connectors is a reasonable DIY first step. If a board needs replacement, a Bosch-certified technician is recommended for proper programming. Unauthorized board replacements may void any remaining warranty on the unit.