OBD Guide

B221D

Rain Sensor Module Internal

B221D is an OBD-II diagnostic trouble code meaning: Rain Sensor Module Internal. Common causes: internal electronics failure of the rain sensor module, damage to module wiring or connectors. Estimated repair cost: $56–167.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$56–167 (est.)

Symptoms

  • Automatic wipers do not work correctly
  • Wipers do not turn on automatically when it rains
  • The wipers operate erratically for no apparent reason.
  • Error indication on the dashboard

Causes

  • Internal electronics failure of the rain sensor module
  • Damage to module wiring or connectors
  • Damage to the optical surface of the sensor
  • Module power problems
  • Software error in the module

How to Fix

  1. Check the connectors and wiring harness of the rain sensor module
  2. Clean the optical surface of the sensor from dirt
  3. Check the power supply and ground of the module
  4. Scan the system for additional errors
  5. Replace the rain sensor module if necessary
  6. Flash or update module software (if required)

FAQ

What does the B221D code mean?

B221D is an OBD-II diagnostic trouble code that indicates: Rain Sensor Module Internal

What causes a B221D error code?

The most common causes of B221D include: Internal electronics failure of the rain sensor module; Damage to module wiring or connectors; Damage to the optical surface of the sensor; Module power problems.

How do I fix a B221D diagnostic trouble code?

To fix B221D: Check the connectors and wiring harness of the rain sensor module. Clean the optical surface of the sensor from dirt. Check the power supply and ground of the module. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with B221D?

Limited driving only, diagnose soon

How much does it cost to fix B221D?

The estimated repair cost for B221D is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat