OBD Guide

U1A03

Telematics Control Unit SIM Card

U1A03 is an OBD-II diagnostic trouble code meaning: Telematics Control Unit SIM Card. Common causes: sim card missing or incorrectly installed, sim card damaged. Estimated repair cost: ~$167.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
~$167 (est.)

Symptoms

  • Lack of connection to car Internet services
  • Emergency call (eCall) does not work
  • Error message on the instrument panel display
  • No navigation map updates
  • Remote services do not work through the mobile application

Causes

  • SIM card missing or incorrectly installed
  • SIM card damaged
  • Connection problems at TCU connector
  • Malfunction of the telematics control unit
  • Damage to the wiring harness to the telematics unit

How to Fix

  1. Check the presence and correct installation of the SIM card
  2. Try rebooting the telematics system
  3. Check the connection of the TCU connectors
  4. Test the operation of the SIM card in another device
  5. Repair only from an authorized dealer

Related codes

FAQ

What does the U1A03 code mean?

U1A03 is an OBD-II diagnostic trouble code that indicates: Telematics Control Unit SIM Card

What causes a U1A03 error code?

The most common causes of U1A03 include: SIM card missing or incorrectly installed; SIM card damaged; Connection problems at TCU connector; Malfunction of the telematics control unit.

How do I fix a U1A03 diagnostic trouble code?

To fix U1A03: Check the presence and correct installation of the SIM card. Try rebooting the telematics system. Check the connection of the TCU connectors. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U1A03?

Yes, but get it checked soon

How much does it cost to fix U1A03?

The estimated repair cost for U1A03 is ~$167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat