OBD Code B1957: Seat Front Up/Down Potentiometer Feedback Circuit Short To Ground

Q: What are the symptoms of fault code B1957?

Seat up/down control doesn't respond or moves erratically, Seat memory position fails to save or recall, Dashboard warning light or seat adjustment malfunction indicator

Q: How do I fix OBD fault code B1957?

Inspect and reseat the seat control module connectors for corrosion or loose pins causing ground contact.. Check the potentiometer cable for damage, pinches, or exposed wires shorting to vehicle frame or seat metal.. Replace the faulty potentiometer unit if wiring is intact but voltage remains grounded.

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What This Actually Means

In plain language — no jargon

The seat's up/down position sensor is sending a constant ground signal instead of varying voltage, like a broken volume knob stuck at zero. The car's computer can't tell where the seat is positioned.

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Symptoms You May Notice

3 known symptoms for this code

Seat up/down control doesn't respond or moves erratically

Seat memory position fails to save or recall

Dashboard warning light or seat adjustment malfunction indicator

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How Your ECU Detects This

Technical sensor logic and voltage thresholds

The ECU monitors voltage from the seat potentiometer, which should vary as the seat moves up or down. A short to ground pulls the voltage to 0V regardless of seat position, preventing the ECU from calculating actual seat location. The module expects a variable signal between 0.5V and 4.5V.

Voltage & Parameter Thresholds

Parameter	Normal Range	Fault Condition
Potentiometer feedback voltage	0.5V to 4.5V (variable with position)	Constant 0V or below 0.2V
Signal continuity to ground	High resistance (>10 kΩ)	Low resistance (<1 kΩ) indicating short

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Diagnostic & DIY Fix Guide

Check these in order — from cheapest to most complex

1

Wiring harness connectors

Inspect and reseat the seat control module connectors for corrosion or loose pins causing ground contact.

2

Potentiometer wiring

Check the potentiometer cable for damage, pinches, or exposed wires shorting to vehicle frame or seat metal.

3

Seat potentiometer

Replace the faulty potentiometer unit if wiring is intact but voltage remains grounded.

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When to See a Professional Mechanic

Not all fault codes are safe to DIY

Code B1957 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 B1957

What happens after you fix the fault

Once the fault is repaired, B1957 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.