OBD Guide

U0421

Invalid Data Received From Suspension Control Module A

U0421 is an OBD-II diagnostic trouble code meaning: Invalid Data Received From Suspension Control Module A. Common causes: problems with wiring to the suspension module, suspension control module malfunction. Estimated repair cost: $56–278.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$56–278 (est.)

Symptoms

  • Check Engine Light Is On
  • Incorrect suspension operation
  • Reduced riding comfort
  • Errors in other systems
  • Additional fault codes appear

Causes

  • Problems with wiring to the suspension module
  • Suspension control module malfunction
  • Bad contacts in connectors
  • Software errors in the module
  • Problems with the CAN bus

How to Fix

  1. Check connections and wiring to suspension module
  2. Scan all modules for additional errors
  3. Update suspension module software
  4. Check power supply and grounding of the module
  5. Replace suspension control module if necessary

Related codes

Error U0421 by Vehicle Brand

FAQ

What does the U0421 code mean?

U0421 is an OBD-II diagnostic trouble code that indicates: Invalid Data Received From Suspension Control Module A

What causes a U0421 error code?

The most common causes of U0421 include: Problems with wiring to the suspension module; Suspension control module malfunction; Bad contacts in connectors; Software errors in the module.

How do I fix a U0421 diagnostic trouble code?

To fix U0421: Check connections and wiring to suspension module. Scan all modules for additional errors. Update suspension module software. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U0421?

Yes, but get it checked soon

How much does it cost to fix U0421?

The estimated repair cost for U0421 is $56–278. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat