DTC P2603: General Description
The electric engine coolant pump varies revolution speed according to the outputs signal. The PCM outputs signal (EWPC) to the electric engine coolant pump and feeds back the revolution speed (EWP REV) from the electric engine coolant pump to control the revolution speed. Since the flow rate of the pump is in proportion to the revolution speed, the flow rate increases as the revolution speed is raised. If the electric engine coolant pump revolution speed is more than a specified value continuously for the prescribed time when the PCM outputs stop signal to the electric coolant pump, the PCM detects a malfunction and stores a DTC.