U0155: OBD-II code U0155 flags loss of communication with the instrument panel cluster — the network can no longer see the dashboard cluster module.

Symptoms

• Gauges may freeze, sweep to zero, or read incorrectly (speedometer, tachometer, fuel gauge, temperature).
• Warning lamps and dashboard messages may not display correctly, or may be stuck on regardless of vehicle state.
• The odometer may not update and the trip computer may show no data or error messages.

Common causes

• A failed cluster module — the module itself has gone offline due to internal failure.
• A CAN bus fault (broken wire or short) between the cluster and the rest of the network.
• Loss of power or ground at the cluster, often after a coolant leak or interior water intrusion at the dashboard.

What to do?

Confirm the cluster has power and ground. Check its fuse. Measure CAN bus continuity. If the cluster is dead but power, ground, and bus all check good, replace and program the new cluster to the vehicle VIN.