U0189: Lost Communication with Digital Disc Player C
Diagnostic trouble code U0189 indicates a loss of communication with the digital disc player or changer module 'C' on the vehicle's data bus. This module is part of the infotainment system and typically communicates via CAN, LIN, or MOST networks, depending on the vehicle architecture. The 'C' designation suggests multiple similar audio modules exist, with this being the third in hierarchy. The master control module (usually the radio, infotainment module, or BCM) detects the absence of expected messages over a set monitoring period. The fault may be intermittent or permanent.
1. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.
2. Most Common Causes
- Faulty digital disc player/changer module 'C' (internal power supply or microprocessor failure)
- Open or shorted wiring in the communication bus (CAN-H, CAN-L, LIN, or MOST data lines) to the module
- Corroded, loose, or disconnected module connector
- Missing or incorrect CAN bus termination resistor (if applicable to this sub-network)
- Faulty master control module that manages communication with the audio module
- Electromagnetic interference or harness damage from chafing, moisture, or previous repairs
- Voltage variation in the vehicle electrical system affecting module communication
3. Symptoms You Will Notice
- Digital disc player or changer 'C' does not respond or operate
- Infotainment system may display 'No Communication' or similar error for the affected module
4. Step-by-Step Diagnosis
Scan for all stored codes and note any related communication or power supply codes
Check the module's power and ground circuits using a multimeter
Inspect the communication bus wiring and connector for damage, corrosion, or looseness
Verify CAN bus termination resistance (if applicable) at the module or network endpoints
Test the module by substituting a known-good unit or using a scan tool to attempt communication
Check for voltage fluctuations or electrical interference from other components
5. Frequently Asked Questions
Is it safe to drive?▼
Yes, it is generally safe to drive. The fault only affects the digital disc player module, not critical safety systems. However, the infotainment feature may be inoperative.
How much does it cost to fix?▼
Costs vary widely: from $50–$150 for a connector repair or wiring fix, to $200–$600 for module replacement, plus diagnostic fees ($100–$200).