U0186

Lost Communication With Audio Amplifier A

Q: Can I just clear U0186?

You can clear it, but if the module is still offline the code returns as soon as the network looks for it. Fix the power, wiring, or module first.

Communication network Generic OBD-II Low

What it means

U0186 means the vehicle's network has stopped receiving expected messages from the audio amplifier. That module powers the speakers in the sound system. You get no sound or distorted/low audio, but nothing about driving is affected.

Low

Can I keep driving? Yes — this only affects audio. The vehicle drives normally; you'll just have no or degraded sound.

Real-world scan data

Seen in

scans in the past year

Found in

<0.1%

of scans

<0.1%

of scans that found faults

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Warning light or message related to the affected system
The audio amplifier's features stop working or work intermittently
Stored 'lost communication' code in the module that reports the fault
No sound, or distorted/low audio from the speakers

Common causes

Most likely first

Power or ground fault feeding the audio amplifierLikely
Damaged wiring or a loose/corroded connector at the audio amplifierCommon
Break in the CAN/bus wiring between the module and the rest of the networkCommon
The audio amplifier itself has failed internallyLess often
Low battery voltage or a recent battery disconnect knocking modules off the busLess often

How to diagnose & fix

Work through it in order

Check battery voltage and charge; a weak battery or recent disconnect is a common, easy cause.
Scan all modules and confirm whether only the audio amplifier is missing or several are — that narrows wiring vs. module.
Verify power and ground at the audio amplifier's connector.
Inspect the connector and harness to the audio amplifier for damage, corrosion, or backed-out pins.
Check for a manufacturer software update or reflash; if wiring and power are good, replace the failed module. Clear and re-test.

FAQ

Quick answers

Is it safe to drive with U0186?+

Yes — this only affects audio. The vehicle drives normally; you'll just have no or degraded sound.

Can I just clear U0186?+

You can clear it, but if the module is still offline the code returns as soon as the network looks for it. Fix the power, wiring, or module first.

Read & clear U0186 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX