What F90 Means
F90 is listed for the FC6 configuration of the DW60 as a checksum communication error - the controller has compared a block of received data against its own check value and found they disagree. The manual's instruction is to reset the product by switching it off at the wall, and to replace the controller only if the problem comes back.
Common Causes of F90
- Data corrupted in transit between boards
- A brief supply interruption during a write
- A controller that has begun to fail
🔧 One Safe Check You Can Try
Do exactly what the manual asks: switch the machine off at the wall or at the breaker, leave it a couple of minutes, and switch it back on. That is the documented first response and it resolves the transient version of this problem.
⚠ Why You Shouldn't Go Further Than That
- The controller sits behind a splash-sealed housing, and that housing must be off supply before it is opened and resealed properly afterwards.
- A checksum error that returns is a sign, not a diagnosis, so the supply quality is worth checking before a board is condemned.
- Ordering a controller without the exact model and configuration reference is how the wrong revision ends up fitted.
- A board seated with one connector a row out can produce entirely new problems that mask the original one.
Opening a panel to inspect or repair something yourself doesn't automatically cancel your manufacturer's warranty — but it can risk accidental damage, and some manufacturers do have specific service conditions. Check your product's warranty terms, or ask us, before deciding.