Lost Communication with Information Center A
The U0156 code indicates that the vehicle's control module has lost communication with the Information Center 'A' module, also known as the driver information display or instrument panel. This module is responsible for showing vehicle data on the central screen, such as fuel economy, trip information, warning messages, and other system data. The loss of communication is detected when the CAN (Controller Area Network) data bus does not receive valid signals from the module for a specified period, as defined by the manufacturer in compliance with SAE J2012 for network communication codes.
1. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.
2. Most Common Causes
- Faulty Information Center 'A' module (infotainment screen or instrument cluster)
- Open, shorted, or abnormal resistance in the CAN bus wiring
- Corroded, loose, or damaged module connector
- Faulty gateway module that manages communication between networks
- Weak battery or voltage fluctuations affecting module startup
- Incomplete or corrupted software update in the information module
- Electromagnetic interference from improperly installed aftermarket accessories
3. Symptoms You Will Notice
- Blank or frozen infotainment screen or instrument cluster
- Missing or inaccurate vehicle data display (e.g., fuel level, speed, warning lights)
4. Step-by-Step Diagnosis
Scan for other related communication codes and check for any stored codes in other modules.
Inspect the CAN bus wiring and connectors for damage, corrosion, or loose connections.
Test battery voltage and charging system; ensure stable voltage (12.6V or higher).
Check for any aftermarket accessories that may cause interference.
If wiring and power are good, suspect a faulty Information Center module or gateway module.
5. Frequently Asked Questions
Is it safe to drive?โผ
Yes, but you may lose important vehicle information and warning messages. Have it diagnosed soon to avoid missing critical alerts.
How much does it cost to fix?โผ
Diagnosis typically costs $100-$150. Repair costs vary: a wiring fix may be $200-$400, while replacing the information center module can range from $500 to $1,500 or more, depending on the vehicle.