B2355

Passenger Mirror Horizontal / Vertical Feedback Potentiometer Circuit Open

Body Chassis/Safety Mirror Control System 🟢 Low — Fix at next service ✅ Safe to Drive
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What This Actually Means

In plain language — no jargon

The passenger side mirror's position sensor has an open circuit, preventing the ECU from reading whether the mirror is pointing up, down, left, or right. It's like a broken volume knob that won't send feedback about its position to your stereo.

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Symptoms You May Notice

3 known symptoms for this code
Passenger mirror does not respond to control inputs
Mirror control switch lights up but mirror won't move
Dashboard warning light for mirror system or fault code display
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How Your ECU Detects This

Technical sensor logic and voltage thresholds

The ECU monitors the potentiometer resistance in the mirror actuator feedback circuit. It expects a variable voltage signal between 0–5V corresponding to mirror position. An open circuit produces no signal, triggering the fault.

Voltage & Parameter Thresholds

ParameterNormal RangeFault Condition
Potentiometer Voltage 0.5–4.5V (varies with position) No signal or infinite resistance (open)
Circuit Continuity Complete path, 100–10kΩ resistance Open circuit, >100kΩ or no continuity
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Diagnostic & DIY Fix Guide

Check these in order — from cheapest to most complex
1
Wiring connector and pins
Inspect the mirror control connector for corrosion, loose pins, or water damage and reseat or clean the connection.
2
Mirror motor/actuator assembly
Remove the mirror panel and test the potentiometer with a multimeter; if open, replace the entire mirror actuator.
3
Wiring harness
Trace the feedback wire from mirror to door module for breaks, pinches, or corrosion; repair or replace damaged sections.
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When to See a Professional Mechanic

Not all fault codes are safe to DIY

Code B2355 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.
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How to Clear Code B2355

What happens after you fix the fault

Once the fault is repaired, B2355 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.