U3535High Voltage System Interlock Circuit L
- Generic OBD-II code · Network
- Turns on the check-engine light
- Can trigger limp mode
- How the car detects it
- U3535 is the umbrella code for interlock circuit L, the eleventh loop. Large vehicles carry many guarded compartments. On New Flyer battery buses the energy storage units sit on the roof at front, centre and rear, and each access door is watched by an interlock limit switch. A service instruction from the bus maker, filed with NHTSA, swaps the switch bracket for one with a stop and bonds a striker plate to the door so the switch is pressed reliably; the same procedure turns a separate HV interlock switch off for lockout. A misadjusted door switch, or a lockout switch not turned back on, can open a loop such as L. Which compartments belong to it is not published.
- What you may notice
- Vehicle or one energy storage unit unavailable after maintenance
- High-voltage system warning on the dashboard
- Fault linked to opening or closing a compartment
- Likely causes
- LikelyDoor or lid limit switch on loop L misadjusted or not actuated
- PossibleManual high-voltage interlock or lockout switch left off after service
- PossibleConnector in loop L not fully latched
- RareController monitoring loop L faulty
- Repair
- Hard · Usually a job for a workshop.Typical cost: €60 – €1,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.