Drivers who encounter a U0156 code usually discover that the vehicle’s primary information display stops responding. The instrument panel may remain dark, flash intermittently, or show a “communication error” message. Warning lights—such as ABS, airbag, or traction‑control indicators—remain off even when a fault exists. Door‑lock and power‑window switches become inoperative, and the driver may be unable to adjust the odometer or speedometer. Because the information center also relays safety‑critical alerts, the malfunction often triggers a service‑engine‑ready (MIL) illumination.
These signs appear suddenly and persist until the underlying communication loss is resolved. The problem does not affect engine power, transmission shifting, or fuel delivery, but it compromises vehicle monitoring and safety‑system warnings.
The vehicle’s high‑speed CAN (Controller Area Network) bus carries data between the Information Center A module and other control units. Corroded pins, broken harnesses, or loose connector clips interrupt this flow, causing the U0156 code. Heat cycling, exposure to moisture, or vibration can degrade the integrity of the harness over time.
Internal component failure—such as cracked solder joints, damaged micro‑controller, or water intrusion—prevents the module from transmitting or receiving messages. When the module cannot acknowledge the network’s heartbeat, the diagnostic scanner records a lost‑communication fault.
Manufacturers periodically release calibration updates for the Information Center A. An incomplete flash, software glitch, or mismatch between the module’s firmware and the vehicle’s VIN can break the handshake protocol, resulting in U0156.
The Information Center A relies on a stable 12 V supply and proper grounding. A failing fuse, weak battery, or high‑resistance ground strap can cause intermittent power loss, which the network interprets as a communication failure.
Connect a factory‑level scan tool and record all stored and pending codes. A lone U0156 often points directly to the information center, but accompanying network‑related codes (e.g., U0100 “Lost Communication With Vehicle Network”) may indicate a broader bus issue.
Measure voltage at the Information Center A’s power pin while the ignition is ON. It should read 12.0‑12.6 V. Check ground resistance; values above 0.2 Ω suggest a poor ground that must be cleaned or re‑torqued.
Visually examine the harness for chafing, corrosion, or broken clips. Use a multimeter to confirm continuity on each CAN‑high and CAN‑low wire (typically 2 Ω to 3 Ω termination). Apply dielectric grease to connector pins and reseat the module plug.
Using the scan tool, command the Information Center A to send a diagnostic request and observe the response time. A timeout or “no response” confirms a loss of communication.
If power, ground, and wiring are sound, re‑flash the module with the latest software version matching the vehicle’s VIN. This step resolves corrupted firmware without hardware replacement.
When re‑programming fails or internal diagnostics (e.g., built‑in self‑test) indicate hardware failure, replace the Information Center A. Ensure the replacement unit is VIN‑matched and pre‑programmed to the vehicle’s calibration set.
After repair or replacement, clear all codes and perform a drive cycle. Confirm that the instrument cluster illuminates, warning lights function, and door‑lock/window commands respond. Re‑scan to ensure the U0156 code does not reappear.
Typical costs
If the Information Center A fails its built‑in self‑test, shows physical damage, or continues to miss network handshakes after a clean re‑flash, replacement is the most reliable solution. Repeated repairs on a compromised board rarely restore long‑term stability, especially when moisture or heat‑induced solder cracks are present.
Modern control modules are complex and integrated with security and immobilizer systems. That’s why choosing a replacement isn’t only about the hardware—it’s about correct programming and compatibility. Flagship One specializes in VIN‑matched control modules, providing a plug‑and‑drive solution backed by warranty. Their pre‑programmed units eliminate dealer‑only programming delays and ensure the new Information Center A communicates flawlessly with the vehicle’s network.
Service Recommendation: Most issues related to this fault are diagnosed and corrected through inspection, wiring repair, and calibration rather than module replacement. For modules not typically replaced through aftermarket suppliers, diagnosis and repair should be performed by a certified automotive technician with access to factory service information and tooling.