OBD Guide

B3971

Folding Top Position Sensor

B3971 is an OBD-II diagnostic trouble code meaning: Folding Top Position Sensor. Common causes: position sensor malfunction, broken or damaged wiring harness. Estimated repair cost: $56–167.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$56–167 (est.)

Symptoms

  • Retractable roof failure to operate
  • Error message on the dashboard
  • Problems with automatic opening/closing of the roof

Causes

  • Position sensor malfunction
  • Broken or damaged wiring harness
  • Contact corrosion
  • Problems with the control unit

How to Fix

  1. Check the condition of the sensor and its connection
  2. Check the integrity of the wiring harness
  3. Replace sensor if necessary
  4. Update the control unit firmware

Related codes

Error B3971 by Vehicle Brand

FAQ

What does the B3971 code mean?

B3971 is an OBD-II diagnostic trouble code that indicates: Folding Top Position Sensor

What causes a B3971 error code?

The most common causes of B3971 include: Position sensor malfunction; Broken or damaged wiring harness; Contact corrosion; Problems with the control unit.

How do I fix a B3971 diagnostic trouble code?

To fix B3971: Check the condition of the sensor and its connection. Check the integrity of the wiring harness. Replace sensor if necessary. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with B3971?

Yes, but get it checked soon

How much does it cost to fix B3971?

The estimated repair cost for B3971 is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat