The U0159 code indicates that the vehicle’s diagnostic system has lost communication with the Parking Assist Control Module (PACM). It is a network‑communication error that means the modules can no longer exchange data on the CAN bus.
The PACM itself has failed or its internal circuitry is damaged, preventing it from sending or receiving messages on the network.
Damaged, frayed, or corroded wiring between the PACM and other modules can interrupt signal transmission.
If the parking sensors or blind‑spot modules are not properly connected, the PACM may lose communication with the sensor network.
A surge or short in the power supply to the PACM can cause the module to shut down and lose communication.
An outdated or corrupted firmware version in the PACM can lead to intermittent loss of communication.
While rare, a fault in the main engine control unit that manages the CAN bus can result in a U0159 code, but this is typically the last resort after all other causes are ruled out.
No, the PCM is rarely the cause. Most U0159 codes result from a faulty Parking Assist Control Module or damaged wiring. The PCM is only considered after all other components have been ruled out.
A reset will clear the code but does not address the underlying communication loss. The problem will reappear unless the root cause is repaired.
Standard OBD‑II scan tools can read U0159 and provide communication status, but dedicated diagnostic equipment may be needed for detailed module testing.