Code P1000 is not a malfunction code, but a status indicator used by manufacturers to signify that the on-board diagnostics (OBD) system has not yet completed its self-tests. It typically appears after the engine control module has been reset, the battery has been disconnected, or the software has been updated.
Disconnecting the battery removes power from the volatile memory, resetting the OBD monitors.
Using a scan tool to clear diagnostic trouble codes also clears the readiness monitors.
Flashing the engine control module with new firmware resets the internal diagnostic counters.
The vehicle has not been driven under the specific conditions required for the computer to verify all emissions systems.
Internal failure of the PCM preventing the recording of monitor completion, though this is extremely rare for this specific code.
Generally, no. It is a status flag indicating that the computer needs more driving data to verify that all emissions systems are working correctly.
Clearing the code will not fix the underlying issue; the code will return until the required drive cycle is completed and the monitors are set.
No. Replacing the PCM is almost never the correct fix for P1000, as the code is a result of a reset status rather than a hardware failure.