What This Actually Means
In plain language — no jargon
The seat's up/down position sensor has lost electrical connection, like a broken wire in a remote control. The car can't tell where your seat is positioned.
Symptoms You May Notice
3 known symptoms for this code
Seat up/down buttons don't work or respond inconsistently
Seat memory preset fails to recall correct position
Warning light or fault code displayed on dashboard
How Your ECU Detects This
Technical sensor logic and voltage thresholds
The ECU monitors the potentiometer voltage from the seat up/down actuator to track seat height position. It expects a variable voltage signal (typically 0.5-4.5V) that changes as the seat moves. An open circuit causes zero or no signal, triggering the fault.
Voltage & Parameter Thresholds
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Potentiometer Voltage | 0.5V to 4.5V (varies with position) | No signal or out-of-range voltage |
| Circuit Continuity | Continuous signal detected | Open circuit detected |
Diagnostic & DIY Fix Guide
Check these in order — from cheapest to most complex
1
Potentiometer connector
Inspect and reseat the connector at the seat motor; corrosion or loose pins often cause open circuits.
2
Wiring harness
Check the wiring between seat motor and ECU for breaks, cuts, or damaged insulation.
3
Potentiometer sensor
Replace the faulty potentiometer if continuity test fails and wiring is intact.
When to See a Professional Mechanic
Not all fault codes are safe to DIY
Code B1955 is a low-severity fault. Your vehicle is generally safe to drive to a workshop for diagnosis. However, do not ignore it indefinitely — low-severity codes often indicate developing problems that become expensive if neglected. Book a diagnostic appointment within 2–4 weeks. If you notice any additional symptoms (rough running, power loss, unusual smells), treat it as higher priority.
Safety note: OBD-II codes identify the system or circuit where a fault was detected — they do not always identify the exact failed component. A professional mechanic using live sensor data will diagnose the root cause more accurately than replacing parts based on the code alone.
How to Clear Code B1955
What happens after you fix the fault
Once the fault is repaired, B1955 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.
The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.
✅ Safe to Clear When
- Fault has been diagnosed and repaired
- You want to confirm the repair worked
- Code appeared after a sensor was cleaned
⚠️ Do Not Clear When
- Preparing for an emissions/PUC test
- Root cause is still undiagnosed
- Check engine light is flashing
Emissions test note: Clearing codes resets OBD readiness monitors. Most vehicles need 50–100 km of mixed driving before monitors complete. Do not clear codes immediately before an emissions or PUC inspection.