U0453 indicates that the powertrain control module (PCM) or another control module has received invalid or implausible data from the left side restraints control module, which monitors and deploys left-side airbags and seat belt pretensioners. This code typically points to a communication fault on the vehicle's data bus rather than a deployment event.
Internal failure of the module can cause it to send corrupted or missing data on the communication bus.
Open circuits, shorts to ground or power, or corroded pins in the harness between the module and the data bus can disrupt communication.
Insufficient voltage or high resistance on the module's power or ground circuits can cause erratic operation and invalid data transmission.
A short, open, or termination issue on the CAN bus can prevent valid messages from being received by other modules.
Outdated or corrupted control module software may misinterpret valid data; a reprogramming may resolve it if a bulletin exists.
Internal failure of the receiving module's communication circuitry is possible but very rare; consider only after all other causes are eliminated.
The code indicates a communication fault; the restraint system may be disabled, so deployment could be compromised. Repair is required for proper system function.
Low voltage can cause communication errors, but U0453 specifically references invalid data from the left side restraints module; check battery and charging system as part of diagnosis.
No. The PCM/ECM is rarely the root cause; the fault is almost always in the left side restraints module, its wiring, or the data bus. Replace the PCM/ECM only after all other causes are ruled out.
Clearing the code will not fix the underlying fault; the airbag light will likely return and the restraint system may remain disabled. Diagnose and repair before relying on the system.