OBD Guide

P0703

Brake Switch B Circuit

P0703 is an OBD-II diagnostic trouble code meaning: Brake Switch B Circuit. Common causes: faulty brake light switch, open or short circuit in wiring. Estimated repair cost: $9–33.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$9–33 (est.)

Symptoms

  • Cruise control doesn't work
  • Problems with gear shifting (on cars with automatic transmission)
  • Check Engine Light Is On
  • Brake lights may not work correctly
  • The engine does not start (in some cases)

Causes

  • Faulty brake light switch
  • Open or short circuit in wiring
  • Poor contact in connectors
  • Problems with the transmission control module
  • Corrosion of switch contacts

How to Fix

  1. Check the operation of the brake lights
  2. Inspect the wiring and connectors of the switch
  3. Check the resistance of the brake light switch
  4. If necessary, replace the switch
  5. Reset the error code and check if it returns

Related codes

Error P0703 by Vehicle Brand

FAQ

What does the P0703 code mean?

P0703 is an OBD-II diagnostic trouble code that indicates: Brake Switch B Circuit

What causes a P0703 error code?

The most common causes of P0703 include: Faulty brake light switch; Open or short circuit in wiring; Poor contact in connectors; Problems with the transmission control module.

How do I fix a P0703 diagnostic trouble code?

To fix P0703: Check the operation of the brake lights. Inspect the wiring and connectors of the switch. Check the resistance of the brake light switch. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P0703?

Limited driving only, diagnose soon

How much does it cost to fix P0703?

The estimated repair cost for P0703 is $9–33. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat