U0053 indicates that the voltage on Vehicle Communication Bus C has exceeded the expected high threshold. This typically means a short to power or an open circuit on the bus wiring, preventing normal module communication on that network.
A power circuit has contacted the CAN high or CAN low wire of Bus C, pulling the bus voltage above specification.
Corrosion, bent pins, or physical damage at a module connector creates high resistance or a partial short to power.
A module on Bus C has an internal failure that drives the bus lines to a high voltage state.
A broken wire or disconnected terminal leaves the bus floating, which can be interpreted as a high voltage condition by other modules.
An improperly installed accessory (e.g., telematics, tuner) injects voltage onto the bus lines.
The gateway or master module for Bus C has a genuine internal failure, but this is uncommon and should be confirmed only after wiring and other modules are ruled out.
Almost never. U0053 is a bus wiring or module transceiver issue. The PCM/ECM is rarely the cause; replace it only after thorough bus and node testing confirms an internal fault.
Indirectly. Excessive system voltage from a failing alternator regulator can push bus voltage high, but the code usually points to a localized short on the bus itself rather than a global charging issue.
Some vehicles set this code when a non-critical module (e.g., infotainment, door module) drops off Bus C. The primary powertrain functions may remain unaffected.
It depends on which systems are on Bus C. If safety-related modules (ABS, stability control, transmission) are offline, driving is not recommended until the bus is restored.