Skip to content

U0253 – Lost Communication With Accessory Protocol Interface Module (OBD2)

U0253 means "Lost Communication With Accessory Protocol Interface Module". These codes are stored when a control unit stops receiving messages from an infotainment module – radio, amplifier, antenna module, media players, phone or telematics.

Last updated

U0253 quick summary

Fault codeU0253
MeaningLost Communication With Accessory Protocol Interface Module
SystemNetwork / CAN Bus
VehiclesGeneric OBD2
SeverityLow
Can I drive?Yes. Only infotainment functions are affected.
Repair cost€0 – €800

What 'lost communication' codes with infotainment modules mean

Infotainment modules communicate over CAN, MOST or other bus systems. If one goes silent, others store a U018x or U019x code. Symptoms are usually limited to audio, navigation, phone or telematics functions not working.

On ring networks such as MOST, a single failed module can break the whole ring and silence all infotainment functions.

Causes include failed modules, removed or retrofitted equipment without coding, water damage, low voltage and wiring problems.

Symptoms of U0253

  • No sound, radio or navigation
  • Phone or telematics not working
  • Display blank
  • Code stored in several modules
  • Battery drain (module not sleeping)

Most common causes of U0253 (most likely first)

Mechanic's Pro Tip

After removing or replacing an infotainment module, update the installation list (coding) in the gateway – otherwise the car keeps looking for the missing module and stores lost communication codes.

  1. 1.Failed infotainment module

    Most likely

  2. 2.Module removed or retrofitted without coding

  3. 3.Broken ring network (MOST)

  4. 4.Low battery voltage

  5. 5.Wiring or connector fault

Step-by-step diagnostic guide

  1. 1

    Scan all modules

    Check which infotainment modules respond.

  2. 2

    Check battery voltage

    Make sure the battery is healthy.

  3. 3

    Check recently changed equipment

    Check whether a radio, amplifier or phone module has been replaced or removed.

  4. 4

    Check power and network

    Check fuses, supply, ground and the bus or fibre-optic connections.

  5. 5

    Repair and code

    Replace or repair the module and update the coding/installation list.

How do I read fault codes? →Where the OBD2 port is, which scanner to use and how to read and clear codes step by step.

Frequently asked questions

Can I keep driving with U0253?

Yes. Only infotainment functions are affected.

How much does it cost to fix U0253?

Typical repair costs are 0 € – 800 €, depending on the cause and the vehicle. The most common fixes are: failed infotainment module; module removed or retrofitted without coding; broken ring network (MOST). Always confirm the cause with the tests above before buying parts.

Does an infotainment code affect the engine?

No. Only audio, navigation, phone or telematics functions are affected.

Why does the code appear after a radio change?

The gateway still expects the original module; the coding must be updated.

What is the difference between U0253 and similar codes?

U0253 belongs to a group of codes for the same component that differ in the type or location of the fault: U0237 – Lost Communication With Digital Audio Control Module 'C'; U0238 – Lost Communication With Digital Audio Control Module 'D'; U0239 – Lost Communication With Digital Audio Control Module 'E'; U0240 – Lost Communication With Digital Audio Control Module 'F'; U0255 – Lost Communication With Front Display Interface Module; U0256 – Lost Communication With Front Controls Interface Module 'A'. The tests on this page apply to the whole group; the type of fault tells you where to start.

Related fault codes

This guide is for information only. Working on vehicles can be dangerous — if you are unsure, have the car checked by a qualified mechanic. Values can differ between model years; always check the manufacturer's repair information.