FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.

Principles of Operation

PRINCIPLES OF OPERATION

The vehicle is equipped with a powertrain control module (PCM)-controlled charging system. 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 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 third pin on the voltage regulator, the A circuit pin, is a dedicated battery voltage sense line.

Positive Battery Output (B+) Terminal Circuit 38 (BK/OG)
The generator output voltage is supplied through the positive battery output (B+) terminal circuit 38 (BK/OG) on the rear of the generator to the battery and electrical system.

A Circuit 1818 (WH/BK)
This is the A terminal battery voltage sense circuit and is used to sense battery voltage.

Circuit 1817 (YE)
The GEN MON circuit communicates the generator load and error conditions to the PCM.

I Circuit 1816 (YE/LB)
This is the GEN COM circuit. The PCM determines the optimal voltage setpoint for the charging system and communicates this information to the voltage regulator via the GEN COM circuit.