U0262: Lost Communication With Audio Amplifier B

What it means

A control module has stopped receiving expected messages from audio amplifier B. The code identifies the communication loss; audio output routed through that amplifier may be affected.

How it works

Audio amplifier B receives network messages used to coordinate audio functions and sends amplified sound to its assigned speakers. U0262 sets when another module stops receiving expected messages from amplifier B, which can interrupt sound on that amplifier's channels while leaving other audio functions available.

Common causes

Most likely first.

1. Bus wiring open or shorted
2. Module without power or ground
3. Module failed

Symptoms

• Audio output through the amplifier may be unavailable or limited
• A warning may appear depending on the vehicle

How to diagnose it

1. Scan all modules and note whether U0262 is current, along with any infotainment, network, or low-voltage faults.
2. Check whether audio is missing only from speakers served by amplifier B and whether the amplifier responds to a scan tool.
3. Inspect amplifier B's connector and accessible bus wiring for a loose plug, corrosion, water intrusion, or physical damage.
4. Check the amplifier's power and ground circuits to the manufacturer's specification, since an unpowered amplifier cannot communicate.
5. If the supplies pass, test the network wiring to amplifier B for an open or short before replacing it.

Common fixes

• Reconnect or clean a poor connection at audio amplifier B.
• Repair damaged bus wiring to the amplifier.
• Restore a failed amplifier power or ground feed.
• Replace and configure amplifier B if its network and supply circuits test correctly but it remains offline.

Can I keep driving?

This code usually affects audio output rather than driving functions. You can generally continue driving if there are no other warnings, but stop using audio controls if they distract you or interfere with required warning sounds.