Principles of Operation

This vehicle is equipped with a Powertrain Control Module (PCM) controlled charging system. The PCM controlled charging system is a system whereby the PCM determines the optimal voltage setpoint for the charging system and communicates this information to the voltage regulator. The PCM controlled charging system is unique in that it has two 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 and the Generator Monitor (GEN MON) line communicates the generator load and error conditions to the PCM. The third pin on the voltage regulator, the A circuit pin, is a dedicated battery voltage sense line.

Circuit Description

B+ Output Terminal Circuit 36 (YE/WH)
Generator output voltage is supplied through the battery positive (B+) output terminal on the rear of the generator to the battery and the electrical system.

Circuit 1182 (OG/YE)
This is the A terminal battery voltage sense circuit and is used to sense battery voltage.

Circuit 3990 (LB/RD)
This is the generator monitor (GEN MON) circuit. The PCM monitors this circuit to determine the generator load and error conditions.

Circuit 1181 (GY/YE)
This is the generator 1 circuit. This terminal is used to turn on the generator initially. Once the generator is turned on, the generator will only turn off when the engine is shut down.