B1956

Seat Front Up/Down Potentiometer Feedback Circuit Short To Battery

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

In plain language — no jargon

The seat's up/down position sensor is sending a signal that's stuck at maximum voltage, like a dimmer switch stuck at full brightness. This prevents the ECU from accurately detecting where the seat is positioned.

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Symptoms You May Notice

3 known symptoms for this code
Seat up/down controls unresponsive or erratic
Seat memory function fails to recall positions
Check engine light or seat control warning illuminated
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How Your ECU Detects This

Technical sensor logic and voltage thresholds

The ECU monitors the potentiometer feedback voltage from the seat actuator, expecting a variable signal between ground and supply voltage that corresponds to seat height. When shorted to battery voltage, the signal remains constant at maximum, preventing the ECU from detecting seat movement or position changes.

Voltage & Parameter Thresholds

ParameterNormal RangeFault Condition
Potentiometer Feedback Voltage 0.5V to 4.5V (variable with seat position) Stuck at or near 5V (battery voltage)
Circuit Resistance Variable 1kΩ to 100kΩ Near 0Ω or shorted path
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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 seat motor connector at the actuator and ECU for corrosion or loose pins.
2
Potentiometer sensor
Replace the faulty seat position potentiometer on the actuator assembly if resistance checks fail.
3
Seat actuator motor assembly
Replace the entire seat motor unit if internal wiring is damaged or potentiometer is non-serviceable.
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When to See a Professional Mechanic

Not all fault codes are safe to DIY

Code B1956 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 B1956

What happens after you fix the fault

Once the fault is repaired, B1956 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.