B0541Passenger Door Ajar Switch Circuit
- Generic OBD-II code · Body
- How the car detects it
- B0541 cannot be traced in public J2012 lists or published manufacturer data. By its title it covers the ajar switch circuit of the front passenger door. Saab's 9-3 monitors that switch as B2991 in the body control module using the driver-side thresholds: 02 for a grounded line under 2.9 V, 05 for an open line or battery short over 10.2 V. Many modern doors have no separate jamb plunger; ArvinMeritor's US20030182863A1 puts the ajar switch on the latch claw, where it changes state roughly halfway between the fully latched and the safety position, so a door that only reached the safety catch still reads as ajar. A latch replacement can therefore be the fix. Driver side: B0540.
- What you may notice
- Passenger door reported open while driving
- Courtesy light does not react to the passenger door
- Alarm cannot be armed or triggers falsely
- Likely causes
- LikelyAjar switch inside the passenger door latch worn
- PossibleDoor only reaching the safety catch due to misaligned striker
- PossibleSwitch wire open or grounded in the hinge passage
- RareBody control module input faulty
- Repair
- Easy · Often possible to do yourself.Typical cost: €40 – €300
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.