OBD Guide

B1C77

Rear Wiper Relay Circuit

B1C77 is an OBD-II diagnostic trouble code meaning: Rear Wiper Relay Circuit. Common causes: faulty rear wiper relay, open or short circuit in the circuit. Estimated repair cost: $22–56.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$22–56 (est.)

Symptoms

  • Rear wiper does not work
  • Rear wiper intermittent operation
  • The malfunction indicator on the dashboard lights up

Causes

  • Faulty rear wiper relay
  • Open or short circuit in the circuit
  • Wiring harness damage
  • Poor contact in connectors
  • Control unit malfunction

How to Fix

  1. Check rear wiper relay
  2. Inspect the wiring harness for damage
  3. Check connections and contacts in the circuit
  4. Replace relay if necessary
  5. Test the operation of the windshield wiper after repair

Related codes

FAQ

What does the B1C77 code mean?

B1C77 is an OBD-II diagnostic trouble code that indicates: Rear Wiper Relay Circuit

What causes a B1C77 error code?

The most common causes of B1C77 include: Faulty rear wiper relay; Open or short circuit in the circuit; Wiring harness damage; Poor contact in connectors.

How do I fix a B1C77 diagnostic trouble code?

To fix B1C77: Check rear wiper relay. Inspect the wiring harness for damage. Check connections and contacts in the circuit. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with B1C77?

Limited driving only, diagnose soon

How much does it cost to fix B1C77?

The estimated repair cost for B1C77 is $22–56. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat