U0187 is a generic OBD-II network communication fault code that means Lost Communication With CD Player / Changer Module. The vehicle network has detected that communication with the CD player or changer system has been interrupted.
U0187 is a U-code network fault, not a conventional engine fault. Depending on the vehicle, the CD player or CD changer may be a separate electronic module or may be integrated into the radio or infotainment unit. The exact system architecture, fuse location, wiring arrangement, and diagnostic procedure depend on the vehicle manufacturer and model year.
Fault Code Description
U0187 = Lost Communication With CD Player / Changer Module.
Code type: Generic OBD-II Network Communication Code.
Likely fault location: CD player or changer system, separate CD module where equipped, radio/infotainment module, power supply, ground circuit, fuse, communication wiring, or related connectors.
The phrase Lost Communication means that one or more control modules are no longer receiving the expected network messages from the CD player or changer system. It does not automatically mean that the CD mechanism itself has failed.
What Does U0187 Mean?
Depending on the vehicle design, the CD player or changer can communicate with the radio, infotainment system, audio amplifier, BCM, gateway, or other electronic modules through the vehicle communication network.
If the CD system loses power, ground, or communication, another control module may detect that its expected messages are missing and store U0187.
In some vehicles, the CD player is integrated directly into the radio or infotainment unit. In that situation, there may be no separate CD Player / Changer Module to locate or replace.
Symptoms of U0187
- CD player does not operate.
- CD changer is not recognized by the audio system.
- CD playback is unavailable.
- Radio or infotainment system may display an audio-system error.
- Audio functions may operate intermittently.
- CD-related functions may disappear from the infotainment system.
- The CD system may not communicate with the scan tool when a separate module is used.
- Multiple U-codes may be stored.
- Other infotainment functions may be affected on some vehicles.
Common Causes of U0187
- Blown CD or audio-system fuse.
- Failed CD player or changer module where separately equipped.
- Fault inside an integrated radio or infotainment unit.
- Loss of battery power to the audio system.
- Loss of ignition or wake-up power.
- Poor module ground.
- Open communication circuit.
- Short circuit on the vehicle communication network.
- Loose or damaged connector.
- Corroded electrical terminals.
- Damaged wiring.
- Water intrusion around the module or wiring.
- Low or unstable vehicle battery voltage.
- Software or configuration problem.
How to Fix U0187
1. Scan the Vehicle
Perform a complete vehicle scan using a professional diagnostic tool. Record U0187 and all other communication or audio-related codes before clearing the fault memory.
2. Determine the Vehicle Audio System Architecture
Before testing or replacing a component, determine whether the vehicle uses a separate CD player/changer module or whether the CD mechanism is integrated into the radio or infotainment module.
Do not assume that every vehicle with U0187 has a separate CD control module.
3. Check Battery Voltage
Verify battery voltage and charging-system operation. Low or unstable voltage can cause electronic audio modules to shut down or temporarily lose communication.
4. Check Power and Ground
Verify the required battery, ignition, or wake-up power and ground connections for the affected CD system, separate module, or integrated radio/infotainment unit.
A missing power supply or poor ground can make a functioning electronic module appear to be offline.
5. Inspect the Connectors
Inspect the relevant radio, infotainment, or CD module connectors for loose terminals, corrosion, bent pins, damaged locking mechanisms, contamination, and water intrusion.
6. Check Communication Wiring
Inspect the communication circuits between the affected audio module and the vehicle network. Look for open circuits, shorts, damaged insulation, poor connections, and wiring damaged during previous repairs.
7. Check Module Communication
Use a compatible scan tool to determine whether the affected CD or audio module responds to diagnostic communication. If a separate CD module is present and cannot be accessed while other modules communicate normally, concentrate on its power, ground, fuse, connectors, and communication circuits.
8. Test Before Replacing the Module
If power, ground, connectors, and network circuits are verified, follow the manufacturer's diagnostic procedure before replacing the CD module or radio/infotainment unit. Some replacement modules require programming, configuration, or security-related procedures.
U0187 Fuse Box Inspection
Checking the vehicle's fuse boxes is an important step when diagnosing U0187. A blown fuse or loss of power to the CD system, radio, or infotainment module can prevent the affected system from operating and communicating with other control modules.
1. Identify the Correct Fuse
Use the vehicle-specific owner's manual or service information to identify the fuses supplying the CD Player, CD Changer, Radio, Infotainment System, or Audio System. Fuse locations can differ between the engine compartment fuse box and the interior fuse box.
2. Inspect and Test the Fuse
Check the suspected fuse for an open element, but do not rely only on visual inspection. Use a test light or multimeter to verify that the fuse has the correct power supply on both sides when the circuit is supposed to be energized.
3. Check for Power at the Affected Unit
If the fuse is good, verify that voltage actually reaches the affected audio unit. This may be a separate CD changer module or the radio/infotainment unit containing the CD mechanism.
A good fuse does not guarantee that power is reaching the module because an open wire, damaged connector, relay, or poor connection may exist between the fuse box and the affected unit.
4. Do Not Repeatedly Replace a Blown Fuse
If the replacement fuse blows again, do not install a higher-rated fuse. Diagnose the circuit for a short circuit, damaged wiring, water intrusion, or excessive current draw before replacing the fuse again.
↓
CD / Radio / Audio System Fuse
↓
Power Supply
↓
Separate CD Module OR Integrated Radio / Infotainment Unit
↓
Vehicle Communication Network
Important: Fuse numbers, ratings, locations, and circuit assignments are vehicle-specific. Always use the correct fuse rating and wiring diagram for the exact vehicle.
U0187 Diagnostic Signal Flow
↓
Vehicle Communication Network
↓
CD Player / Changer System
↓
CD Mechanism
↓
Audio Data
↓
Audio Output
U0187 OBD Live Data
Use a professional scan tool to check whether the affected CD or audio module is listed as an active communicating module. When a separate CD module is equipped, verify whether it responds to diagnostic communication.
Compare its communication status with the radio, infotainment module, audio amplifier, BCM, gateway, and other network modules.
If several audio or network modules report communication failures simultaneously, investigate common power, ground, gateway, battery, or communication-network faults before replacing any module.
U0187 Diagnostic Strategy
Power Supply
Check battery voltage, audio fuses, module power, wake-up circuits, and ground before condemning the CD or radio/infotainment unit.
Communication Network
Inspect communication wiring, connectors, and network integrity when the affected unit's power and ground are confirmed.
System Architecture
Determine whether the CD system uses a separate module or is integrated into the radio/infotainment unit before replacing any component.
Is U0187 Serious?
U0187 is usually low to moderate in severity. The fault generally affects CD or related audio functions rather than the engine, transmission, or conventional braking system.
However, if U0187 is accompanied by other communication codes, the underlying network or power-supply problem should be diagnosed because it may affect additional electronic modules.
Can I Drive With U0187?
In most cases, the vehicle can be driven with U0187 if no other critical warning lights or system faults are present. The main symptoms are normally related to the audio or infotainment system.
U0187 Repair Cost
- Electrical diagnosis: approximately $50–$150+.
- Fuse or simple wiring repair: approximately $20–$150+.
- Connector or communication wiring repair: approximately $50–$300+.
- Separate CD changer/module replacement: approximately $150–$800+ depending on the vehicle and module.
- Radio/infotainment unit replacement: approximately $200–$1,500+ when the CD system is integrated into the main unit.
- Programming or configuration: additional cost may apply.
These are general estimates only. Actual repair costs depend on the vehicle, system design, module type, parts availability, programming requirements, and labor rates.
Common Repair Mistakes
- Assuming every vehicle has a separate CD changer module.
- Replacing the CD player before checking its fuse and power supply.
- Failing to verify module power and ground.
- Ignoring communication wiring.
- Replacing a module without inspecting connectors.
- Ignoring additional U-codes stored in other modules.
- Assuming a mechanical CD problem automatically causes U0187.
- Ignoring water intrusion around the audio module.
- Replacing an integrated radio/infotainment unit without confirming the actual fault.
- Replacing a module without performing required programming or configuration.
Related Codes
- U0184 – Lost Communication With Radio.
- U0185 – Lost Communication With Antenna Control Module.
- U0186 – Lost Communication With Audio Amplifier.
- U0187 – Lost Communication With CD Player / Changer Module.
- U0193 – Lost Communication With Digital Audio Control Module.
FAQ About U0187
What does U0187 mean?
U0187 means Lost Communication With CD Player / Changer Module. It indicates that a control module has detected a loss of expected communication with the CD player or changer system.
Is the CD Player / Changer always a separate module?
No. Depending on the vehicle, the CD player or changer may be a separate electronic module or may be integrated into the radio or infotainment unit. Always verify the vehicle-specific system architecture before testing or replacing a component.
Can a blown fuse cause U0187?
Yes. If the CD system or radio/infotainment unit loses its power supply because of a blown fuse, communication with the affected system may be lost.
Can a weak battery cause U0187?
Yes. Low or unstable voltage can cause electronic audio modules to shut down or temporarily lose communication.
Does U0187 mean the CD player is mechanically defective?
No. U0187 is a communication fault. A mechanical problem with the CD mechanism may cause the CD player not to operate, but power, ground, connectors, and communication circuits should be tested before replacing the module or radio/infotainment unit.
Can communication wiring cause U0187?
Yes. An open, shorted, damaged, or poorly connected communication circuit can interrupt communication with the CD system and trigger U0187.
Can U0187 appear with U0184 or U0186?
Yes. The radio, CD system, and audio amplifier may operate as interconnected parts of the same infotainment system. A common power, ground, communication, or gateway problem can cause multiple U-codes.
Final Takeaway
U0187 should be diagnosed as a CD system communication, power, or network fault rather than automatically assuming that the CD mechanism or a separate module has failed.
Start with the fuse box, battery voltage, power and ground, connectors, and communication circuits. Then determine whether the vehicle uses a separate CD module or an integrated radio/infotainment unit.
If these circuits are correct and the affected audio system remains offline, follow the manufacturer-specific diagnostic procedure to determine whether programming, software correction, or component replacement is required.