B2315

Mirror Passenger Horizontal Feedback Potentiometer Circuit Short to Ground

Body Chassis/Safety Mirror feedback circuit 🟢 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 is shorted to ground, preventing the ECU from reading its actual location. It's like a broken volume knob that always reads zero instead of showing the actual position.

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Symptoms You May Notice

3 known symptoms for this code
Passenger mirror controls unresponsive or erratic
Mirror position feedback inaccurate or stuck
Dashboard warning light for mirror system
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How Your ECU Detects This

Technical sensor logic and voltage thresholds

The ECU monitors the potentiometer voltage feedback from the passenger mirror horizontal actuator to determine mirror position. When shorted to ground, the voltage remains at 0V instead of varying between normal operating levels. The ECU detects this abnormal condition and sets the fault code.

Voltage & Parameter Thresholds

ParameterNormal RangeFault Condition
Potentiometer Voltage 0.5V - 4.5V (variable with position) 0V (stuck at ground/short condition)
Resistance 500Ω - 5kΩ (varying) <50Ω (short to ground)
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Diagnostic & DIY Fix Guide

Check these in order — from cheapest to most complex
1
Wiring harness connector
Inspect and reseat the mirror control module connector; corrosion or loose pins commonly cause ground shorts.
2
Wiring loom/cable
Check for damaged insulation or pinched wires between the door frame and mirror assembly causing short to body ground.
3
Mirror motor/potentiometer assembly
Replace the mirror actuator unit if internal potentiometer is internally shorted to ground.
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When to See a Professional Mechanic

Not all fault codes are safe to DIY

Code B2315 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 B2315

What happens after you fix the fault

Once the fault is repaired, B2315 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.