A loose, corroded, or partially unseated connector at the disc player or changer module, especially after recent audio or dashboard work.; Damage to the CAN bus wiring harness between the player and the network, such as a chafed wire, pinched loom, or rodent-chewed insulation.; A failed disc player or changer module that no longer powers up or no longer transmits on the bus.; Low battery voltage or a weak charging system causing modules to drop offline intermittently and log communication codes.; A blown fuse or poor ground connection supplying the disc player, leaving the module unpowered while the bus itself is healthy.; A fault in another module on the same bus that disrupts network traffic and prevents the player's messages from arriving.; Water intrusion or heat damage at the player's mounting location, which corrodes terminals or damages the module's internal circuitry.

DTC codes / U01xx · Lost communication with a control module / U0189

U0189Lost Communication With Digital Disc Player/Changer Module 'C'

U0189 is a generic network communication code indicating that a control module on the vehicle's data bus has lost contact with the digital disc player or changer module designated 'C'. The module that sets this code expected regular status messages from the disc player over the controller area network (CAN) bus and stopped receiving them for a calibrated period, so it logged a communication failure rather than a fault inside the audio unit itself.

SystemNetwork

Code typeGeneric (all makes)

SeverityLow

Fix difficultyIntermediate

AreaLost communication with a control module

Symptoms you may notice

The infotainment or radio display shows a communication error or the disc player source is greyed out and unavailable.
The CD or DVD changer does not respond to buttons, does not eject, or appears dead while the rest of the audio system works.
An amber or red warning light appears on the dash, often accompanied by a chime and a message about an audio system fault.
Other modules on the same bus may log unrelated communication codes, and the vehicle may show a cluster of warning lights.
Often no symptoms besides the warning light, because the disc player is a convenience module and the vehicle drives normally.
Intermittent loss of audio from the disc source, with the player coming back after the vehicle is restarted or after a bump.

Common causes, most likely first

A loose, corroded, or partially unseated connector at the disc player or changer module, especially after recent audio or dashboard work.
Damage to the CAN bus wiring harness between the player and the network, such as a chafed wire, pinched loom, or rodent-chewed insulation.
A failed disc player or changer module that no longer powers up or no longer transmits on the bus.
Low battery voltage or a weak charging system causing modules to drop offline intermittently and log communication codes.
A blown fuse or poor ground connection supplying the disc player, leaving the module unpowered while the bus itself is healthy.
A fault in another module on the same bus that disrupts network traffic and prevents the player's messages from arriving.
Water intrusion or heat damage at the player's mounting location, which corrodes terminals or damages the module's internal circuitry.

How to diagnose and fix it

Verify battery voltage and charging system output first, because low voltage is a common and cheap-to-check cause of intermittent bus communication codes.
Check the fuse and ground for the disc player or changer module, and confirm the module receives power and ground at its connector.
Inspect and reseat the connectors at the player and at any inline harness junctions, looking for corrosion, pushed pins, or loose terminals.
Perform a wiggle test on the harness while watching live network data or the code status to expose an intermittent wiring fault.
Use a scan tool to check whether the player module is present on the bus and whether other modules are also missing, which separates a single-module fault from a bus-wide problem.
Measure CAN bus resistance and voltage at the player connector to confirm the bus is intact and the module is not shorting or loading the network.
If power, ground, and bus integrity are confirmed and the module still does not communicate, replace or reprogram the disc player module and clear the code.

What U0189 does not always mean

This code does not prove the disc player is bad; a loose connector or a weak battery can set it just as easily, so power and ground checks come before any module replacement.
A single missing module on the bus often points to that module's own power, ground, or connector rather than to the network wiring, because a bus-wide fault would normally set codes in several modules at once.
Aftermarket audio equipment, phone kits, or accessories tapped into the bus wiring are a frequent cause of communication codes on the disc player circuit and are easy to overlook.
The 'C' designation means this is the third disc player or changer module address on the network, so a vehicle with multiple changers can set U0189 for one unit while the others still work.
Clearing the code without repairing the underlying connection often results in the code returning after a few drive cycles, so a repair should be verified over several ignition cycles.

Can I keep driving with U0189?

The vehicle remains safe to drive because the disc player is a convenience module and does not affect steering, braking, or powertrain control. Avoid ignoring repeated warning lights, and have the fault checked soon if other modules begin logging communication codes or if the audio system affects other functions.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.