On the Classic Built-In electronic line, BI-36UFD/S and similar, 90-0-75 points to the model information stored in E2 memory. The board checks that data with a checksum and the numbers do not agree, so it cannot…
On the Classic Built-In electronic line, BI-36UFD/S and similar, 90-0-75 points to the model information stored in E2 memory. The board checks that data with a checksum and the numbers do not agree, so it cannot be sure which model it is controlling. That matters because fan timing, defrost and temperature logic depend on the model data. You may see erratic behavior, features missing, or the code right after a board was replaced.
1. Note 90-0-75 and whether any recent repair was done. 2. Cut power at the breaker for one minute and restore it. 3. Check that both sections reach normal temperature over several hours. 4. If a board was recently installed, tell us the date and part when you call.
90-0-74 covers general stored settings, while 90-0-75 concerns the model identity data. A model-data error affects how the board runs fans and defrost, so it deserves quick attention.
A new board has to be told which model it is in. If that step was missed or entered wrong, 90-0-75 can appear. We can correct the setup on site.
Not always. If the board only needs correct model data, we set it during the visit. If the memory is failing, we quote a replacement board in writing first.
A technician diagnoses it on site and gives you the price in writing before any work starts.