U0215Lost Communication With Door Switch A
- Generic OBD-II code · Network
- How the car detects it
- U0215 is logged when door switch unit A, a keypad with its own small controller, stops answering on the bus. NXP application note AN2205 shows how such a keypad usually works: it is a LIN slave that never speaks unprompted; the body controller asks it roughly every 100 ms and expects a four-byte reply holding key states and LIN error flags. If that reply goes missing, the master records the loss. In the GM manual for the 2011 Saab 9-5 these checks run only between 9 and 16 V, and a history entry is dropped after 50 clean ignition cycles. No manufacturer documents U0215 publicly, and which door carries letter A depends on the maker. U0516 reports invalid data from the same switch. Usually only the keys of one panel fail; no MIL.
- What you may notice
- Window, mirror or lock keys on one panel do nothing
- Panel backlighting stays dark
- Code returns after clearing, sometimes only when the door is moved
- Likely causes
- LikelyLIN or supply wire broken where the harness flexes at the door hinge
- PossibleSwitch unit A without battery feed or ground
- PossibleLIN line shorted to ground or battery (often silences several nodes at once)
- RareElectronics in switch unit A failed
- Repair
- Medium · Often possible to do yourself.Typical cost: €20 – €350
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.