B2319

Mirror Passenger Vertical Feedback Potentiometer Circuit Short to Ground

Body Chassis/Safety Mirror Control 🟢 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 vertical position sensor is sending a constant ground signal to the ECU, like a stuck switch. The mirror control system can't properly read the mirror's position because the circuit is shorted.

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Symptoms You May Notice

3 known symptoms for this code
Passenger mirror won't move vertically or moves erratically
Mirror control switch unresponsive or stuck in one position
B2319 fault code stored in ECU memory
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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 vertical actuator. A healthy circuit returns a variable voltage (typically 0.5-4.5V) that indicates mirror position. When shorted to ground, voltage remains at 0V, preventing position feedback.

Voltage & Parameter Thresholds

ParameterNormal RangeFault Condition
Potentiometer voltage 0.5V to 4.5V (variable with position) 0V (constant ground short)
Circuit resistance Variable 100Ω to 100kΩ Less than 50Ω (shorted condition)
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Diagnostic & DIY Fix Guide

Check these in order — from cheapest to most complex
1
Wiring harness connector
Disconnect and reconnect the mirror control module connector to reseat contacts and eliminate corrosion-related shorts.
2
Mirror motor potentiometer
Replace the faulty vertical feedback potentiometer inside the mirror assembly if connector is clean.
3
Mirror control module
Replace the entire mirror motor assembly if potentiometer replacement doesn't resolve the short.
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When to See a Professional Mechanic

Not all fault codes are safe to DIY

Code B2319 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 B2319

What happens after you fix the fault

Once the fault is repaired, B2319 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.