What F86 Means
F86 is the salt container lid contact. It is the problem that sits behind the on-screen message asking you to close the salt reservoir cap, and Miele’s documentation traces it to a reed switch — usually because the magnet in the salt container lid is missing or the switch has failed.
Common Causes of F86
- Salt container cap not screwed down fully or cross-threaded
- Magnet missing from the cap, often after a non-original cap was fitted
- Reed switch that senses the cap failed
- Salt spilled around the cap seat preventing it seating
🔧 One Safe Check You Can Try
Open the door and check the salt reservoir cap in the base of the tub. Unscrew it and screw it back down firmly, making sure it seats square and that the cap itself is the original one — Miele’s documented cause is a missing magnet, and a replacement cap from elsewhere will not have one.
⚠ Why You Shouldn't Go Further Than That
- If the cap is genuine, correctly fitted and the message persists, the reed switch itself is to blame and that is inside the tub base.
- A cap that is not sealing lets wash water into the salt reservoir, which ruins the softener charge and can corrode what is around it.
- Salt is aggressive to the wrong metals, so spillage around the reservoir is worth clearing thoroughly rather than leaving.
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.
Technical Reference
- Code
- F86
- Appliance
- Miele dishwasher
- Maker documentation
- Miele owner manuals and use & care guides
- Checked
- September 2026
Code meanings can change between control generations. Before acting on a code, match the full model number on your appliance's rating label against the manual for that model. We are an independent repair service, not affiliated with Miele & Cie. KG.