OBD Guide

B3621

Head-Up Display Information Down Switch Circuit

B3621 is an OBD-II diagnostic trouble code meaning: Head-Up Display Information Down Switch Circuit. Common causes: open or shorted wiring harness, faulty switch. Estimated repair cost: $11–56.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$11–56 (est.)

Symptoms

  • Switching information on the display does not work
  • The display does not respond to switch presses
  • Random display glitches

Causes

  • Open or shorted wiring harness
  • Faulty switch
  • Display control module problems
  • Poor connection in connectors

How to Fix

  1. Check the integrity of the wiring harness
  2. Check connector connections
  3. Check the functionality of the switch
  4. Check voltage and ground in the circuit
  5. Replace switch if necessary

Related codes

Error B3621 by Vehicle Brand

FAQ

What does the B3621 code mean?

B3621 is an OBD-II diagnostic trouble code that indicates: Head-Up Display Information Down Switch Circuit

What causes a B3621 error code?

The most common causes of B3621 include: Open or shorted wiring harness; Faulty switch; Display control module problems; Poor connection in connectors.

How do I fix a B3621 diagnostic trouble code?

To fix B3621: Check the integrity of the wiring harness. Check connector connections. Check the functionality of the switch. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with B3621?

Limited driving only, diagnose soon

How much does it cost to fix B3621?

The estimated repair cost for B3621 is $11–56. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat