mypros+
Error code reference

Bosch Refrigerator Error Code F39

Limit switch at top is switched on while the water bowl is being swung down (only appliances up to Eprom…

Bosch codesBosch refrigerator codes

Limit switch at top is switched on while the water bowl is being swung down (only appliances up to Eprom version 5.02).

First step from the service manual

Check limit switches for the water bowl.

The complete diagnostic procedure includes additional test steps, resistance specifications, wiring diagram references, and component test points.

MyPros+ Max

Get the full diagnostic procedure for F39.

  • Step-by-step tests with expected resistance, voltage, and continuity values
  • Wiring diagram references and connector pinouts from the OEM service manual
  • Verified part numbers when replacement is required
Get the full procedure

$29/month · Cancel anytime · Or $9.95 3-day pass

What F39 means on a Bosch refrigerator

The F39 error code on Bosch refrigerators indicates a fault in the automatic water bowl (evaporation tray) swing mechanism. Specifically, the top limit switch is reading as activated during the downward swing cycle of the water bowl, when it should not be engaged in that position. This code applies only to units running EPROM firmware version 5.02 or earlier. The water bowl is a motorized component that rotates or pivots to collect and evaporate condensation water, and its movement is governed by a set of limit switches that signal the control board when the bowl has reached its upper or lower travel boundaries.

When the bowl swings downward, the control board expects the top limit switch to be open (not activated). If the switch reads as closed or activated during this motion, the board interprets it as a positional conflict and triggers F39 to halt the movement and flag the fault. This prevents mechanical damage that could result from the motor continuing to drive the bowl against its mechanical stops or wiring harness.

Common causes include a misaligned or stuck limit switch, a faulty switch that is failing to open properly, wiring harness damage causing a short that holds the switch signal active, or physical obstruction in the bowl swing path that is keeping the mechanism from moving away from the top position. Ice buildup around the mechanism can also hold the bowl or actuate the switch incorrectly. The first diagnostic step is a direct inspection and continuity test of the top limit switch.

Source: manufacturer service documentation.

Common causes of F39

  1. 01

    Faulty top limit switch

    Part replacement

    The top limit switch may have failed internally and is remaining in the closed (activated) position even when the water bowl moves away from the top. Continuity testing of the switch while the bowl is in the lowered position will confirm if it is stuck closed.

  2. 02

    Misaligned limit switch

    Wiring / connection

    Physical misalignment of the switch mounting can cause it to make unintended contact during the downward swing. Inspect the switch bracket and mounting position for any shifting or looseness.

  3. 03

    Wiring harness short or damage

    Part replacement

    A damaged wire or short in the harness connecting the top limit switch to the control board can hold the switch signal in an active state regardless of actual switch position. Inspect the harness for chafing, pinching, or moisture damage.

  4. 04

    Ice or debris obstructing the bowl mechanism

    Wiring / connection

    Ice buildup or foreign debris around the water bowl pivot area can physically prevent the bowl from moving away from the top position, keeping the switch engaged. Inspect the area for obstructions and defrost if necessary.

  5. 05

    Control board misreading switch input

    Part replacement

    In rare cases the main control board may be incorrectly interpreting the limit switch signal due to a board fault. This should only be considered after the switch, wiring, and mechanical components have been ruled out.

See the test procedure for each cause

Frequently asked questions about F39

What does F39 mean on a Bosch refrigerator?
F39 indicates that the top limit switch for the water bowl is registering as activated while the bowl is swinging downward, which is an unexpected signal. This fault applies only to Bosch refrigerators with EPROM firmware version 5.02 or earlier. The refrigerator stops the bowl movement to prevent mechanical damage and alerts you to the fault. The top limit switch and its wiring should be inspected first.
Can I fix the F39 error myself?
A knowledgeable DIYer can begin by inspecting the water bowl area for ice buildup, debris, or visible wiring damage, which are accessible checks that require no specialized tools. Testing the limit switch for proper continuity does require a multimeter and some disassembly. If the switch or wiring is damaged, replacing those components is a moderate repair, but if the control board is at fault, professional service is recommended.
Is it safe to use my Bosch refrigerator while F39 is displayed?
The refrigerator's cooling function may continue to operate, but the water bowl mechanism is halted, which means condensation evaporation could be affected over time. Running the appliance in this condition is not ideal and could lead to water accumulation. It is best to address the fault promptly rather than continuing normal use with the error active.
Will resetting the refrigerator clear the F39 error?
A power reset may temporarily clear the error code, but if the underlying fault with the top limit switch or wiring has not been corrected, the F39 code will return when the water bowl mechanism cycles again. A reset alone is not a fix and should only be used as part of the diagnostic process to observe whether the fault reoccurs immediately.
How much does it cost to repair a Bosch refrigerator F39 error?
Repair costs vary depending on the root cause. Replacing a limit switch is generally a lower cost repair, with parts typically ranging from $15 to $60 and labor adding $75 to $150 depending on the service provider. If the control board requires replacement, costs can rise to the $200 to $500 range including parts and labor. Getting a diagnostic visit first is the best way to get an accurate estimate.

Related Bosch refrigerator codes

All Bosch refrigerator codes
View all 209 Bosch refrigerator codes

78,000+ service manuals · 160,000+ error codes · 55+ brands

Get Started

$29/month · Cancel anytime · Or $9.95 3-day pass