Circuit/System Description

The drive motor generator power inverter module contains two motor control modules. Each motor control module controls and monitors its respective drive motor generator based upon commands from the hybrid powertrain control module. In order for the hybrid powertrain control module to monitor the internal combustion engine speed, motor control module 1 is electrically connected to the crankshaft position sensor signal and reference circuits. The motor control module 1 engine speed information is broadcast to the hybrid powertrain control module over an internal drive motor generator power inverter module communication circuit. Additionally, the hybrid powertrain control module receives engine speed over serial data that is broadcast by the engine control module (ECM) and is based upon the ECM connection to the crankshaft position sensor.

A drive motor generator position sensor is monitored by each motor control module. Each motor control module monitors the angular position, speed and direction of its respective drive motor generator based upon the signals of the resolver-type position sensor.

The hybrid powertrain control module mathematically calculates what engine speed should be based upon the current transmission ratio and the drive motor generator speeds indicated by the drive motor generator position sensors.

The hybrid powertrain control module compares this mathematically calculated engine speed to the sensor-derived serial data ECM engine speed signal and motor control module signal engine speed. If the drive motor generator position sensor speeds are correct, the mathematical equation should accurately calculate engine speed. If the mathematical calculation for engine speed does not match the sensor-derived engine speed, a drive motor position speed sensor error is assumed and this DTC will set.