Principles of Operation
The powertrain control module (PCM) controlled charging system determines the optimal voltage setpoint for the charging system and communicates this information to the voltage regulator. This system is unique in that it has 2 unidirectional communication lines between the PCM and the generator/regulator. Both of these communication lines are pulse-width modulated. The generator communication (GEN COM) line communicates the desired setpoint from the PCM to the voltage regulator. The generator monitor (GEN MON) line communicates the generator load and error conditions to the PCM. The 3rd pin on the voltage regulator, the A circuit pin, is a dedicated battery voltage sense line.
Normal Operation
The generator output is supplied through the battery positive output (B+) circuit 2037 (RD) terminal on the rear of the generator to the battery and electrical system. During normal operation the charging system warning indicator is off with the ignition switch in the RUN position and the engine running. The charging system warning indicator is on with the ignition switch in the RUN position and the engine off.
With the engine running, the charging system warning indicator is off. The sense A circuit 35 (OG/LB) to the generator field coil is 13-15 volts. The S (stator) circuit (internal to the generator) is used to feed back a voltage signal from the generator to the voltage regulator. This voltage is used by the powertrain control module (PCM) to turn off the charging system warning indicator. The battery positive output (B+) circuit 2037 (RD) is the generator output supplied to the battery and electrical system.
The generator output is determined by the voltage of the A circuit 35 (OG/LB). The A circuit voltage is compared to a set voltage internal to the regulator, and the regulator controls the generator field current to maintain the correct generator output. The set voltage varies with temperature and is typically higher in cold temperatures and lower in warm temperatures.
With the engine running, the charging system warning indicator is off. The sense A circuit 35 (OG/LB) to the generator field coil is 13-15 volts. The S (stator) circuit (internal to the generator) is used to feed back a voltage signal from the generator to the voltage regulator. This voltage is monitored by the powertrain control module (PCM) to turn off the charging system warning indicator. The battery positive output (B+) circuit 2037 (RD) is the generator output supplied to the battery and electrical system.
Under normal operation, the charging system warning indicator is on with the key ON and the engine off.
The generator is belt-driven by the engine accessory drive system.
The generator radio suppression equipment reduces interference transmitted through the speakers by the vehicle electrical system.