U0096 indicates a problem with the vehicle's high-speed CAN bus line H, which is used for communication between control modules. The code is set when the vehicle detects a fault or loss of signal on that specific bus line.
Damaged insulation, broken wires, or corroded pins in the bus H harness can interrupt signal integrity and trigger U0096.
The bus relies on proper termination; a loose or corroded resistor can cause signal reflections and loss of communication.
Modules such as the ABS, BCM, or steering control unit may develop internal faults that disrupt bus traffic.
Voltage drops or poor grounding on a module can affect its ability to transmit messages on the bus.
The powertrain control module can generate a bus fault only when its internal circuitry or communication interface fails, which is uncommon.
In most cases the PCM is not the cause; the issue is usually wiring, a connector, or a faulty module on the bus.
Driving may be possible if no drivability problems are present, but the code should be cleared only after the underlying fault is repaired.
Diagnosis time varies with the complexity of the fault but typically requires a few hours to trace bus wiring and test modules.
No, U0096 is a communication network fault and does not directly affect emissions systems.