What it means
A control module has stopped receiving expected messages from information center A. The information center or functions that depend on it may be unavailable.
How it works
Information Center A displays or manages information and functions assigned to that vehicle module, and it exchanges data with other controllers over CAN. U0156 sets when the reporting controller stops receiving expected messages from Information Center A, so its display or dependent features may be unavailable.
Common causes
Most likely first.
- Information center A power or ground fault
- Damaged network wiring or connector
- Information center A failure
- Low system voltage
Symptoms
- Information center display or functions may be unavailable
- Warning lights or messages
- Other communication codes
How to diagnose it
- Scan all modules and note freeze-frame and communication codes to confirm that Information Center A is the module that fails to respond.
- Check whether the information center display or its associated controls are inoperative while other vehicle systems still work.
- Check the 12-volt battery and charging system, then inspect the information center's accessible fuse and connector for a poor fit or corrosion.
- Use a wiring diagram to verify the module's specified power and ground.
- Test the CAN wiring and gateway path to Information Center A using the manufacturer's network procedure.
- If supplies and network are sound, check module response and configuration with a compatible scan tool.
Common fixes
- Restore a weak 12-volt battery or repair its charging fault.
- Replace a blown fuse or repair a poor power or ground connection to Information Center A.
- Reconnect or repair a loose, corroded, or damaged connector.
- Repair a confirmed CAN wiring or gateway routing fault.
- Replace or configure Information Center A only after its power, ground, and network have been verified.
Can I keep driving?
If the vehicle drives normally, you can usually continue cautiously, but do not rely on Information Center A for warnings or features it normally displays. Stop safely if you cannot see essential vehicle warnings or other systems are affected.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.