B0502Left Rear Power Window Circuit Malfunction
- Generic OBD-II code · Body
- How the car detects it
- B0502 has no entry in any accessible J2012 list, and no carmaker describes it, so the code stays unproven. Its title concerns the left rear window circuit. In the Saab 9-3 the left rear door module logs B3210 04 when the motor's up path is open and the glass will not close, and B3543 if the two Hall signals arrive in reverse order for 150 ms, which disables one-touch travel. GM's 2011 9-5 assigns the left rear motor B3215. Microchip's AVR480 note shows why the Hall pulses matter: speed, current and glass position feed the pinch check. FMVSS 118 demands reversal before 100 N for any window that closes on its own. Many rear doors carry a child lockout; a locked-out rear switch is intended and not a fault.
- What you may notice
- Left rear window will not close or will not open
- One-touch function and pinch protection not available
- Window reverses on its own without an obstacle
- Likely causes
- LikelyHall sensor in the motor or its supply faulty
- PossibleLeft rear window motor worn or with an open winding
- PossibleWires broken in the rear door hinge passage
- Repair
- Medium · Often possible to do yourself.Typical cost: €80 – €450
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.