PCM Controlled Generator
PCM Controlled Generator Description:
WITH F TERMINAL
The generator provides voltage to operate the vehicles electrical system and to charge the vehicles battery. A magnetic field is created when current flows through the rotor.
This field rotates as the rotor is driven by the engine, creating an AC voltage in the stator windings. The AC voltage is converted to DC voltage by the rectifier bridge and is supplied to the electrical system at the battery terminal.
The operation of the charging system is monitored by the PCM. The PCM monitors the charging system loads and adjusts the idle speed accordingly. The PCM also sends information to the Instrument Panel (IP) cluster when the charging system is inoperative and the P cluster illuminates the telltale lamp or activates the message center as applicable.
The PCM supplies 5 volts through the L circuit to the generator. If the generator becomes inoperative, the PCM can detect the fault through the L circuit and tells the IP cluster to illuminates the telltale lamp or activates the message center as applicable.
The PCM monitors the duty cycle of the generator through the F circuit. As the generator load increases, the PCM will adjust the idle speed accordingly.
If the voltage telltale or message is on and the (L) terminal voltage is low while the PCM is commanding the generator on for more than 30 seconds OR
If the voltage telltale lamp or message is on and the (F) terminal PWM is less than 5 percent while engine RPM is less than 2500 for more than 30 seconds DTC P0620 will set.
The low battery message may not appear if other messages are being commanded, such as the rear deck lid, driver or passenger doors ajar. Ensure that all doors and compartment lids are completely closed. If the voltage telltale lamp or message is on but no DTCs are set, use the A Diagnostic System Check - Starting and Charging in Engine Electrical, and A Diagnostic System Check Instrument Cluster, or A Diagnostic System Check - Driver Information Systems in Instrument Panel, Gauges, and Console to diagnose the condition.
WITHOUT F TERMINAL
The generator provides voltage to operate the vehicles electrical system and to charge the vehicles battery. A magnetic field is created when current flows through the rotor.
This field rotates as the rotor is driven by the engine, creating an AC voltage in the stator windings. The AC voltage is converted to DC voltage by the rectifier bridge and is supplied to the electrical system at the battery terminal.
The operation of the charging system is monitored by the PCM. The PCM monitors the charging system loads and adjusts the idle speed accordingly. The PCM also sends information to the Instrument Panel (IP) cluster when the charging system is inoperative and tells the IP cluster to illuminate the volts telltale lamp.
The PCM supplies 5 volts through the L circuit to the generator. If the generator becomes inoperative, the PCM can detect the fault through the L circuit and tell the P Cluster to illuminate the volts telltale lamp.
The PCM also monitors the duty cycle of the generator through the L circuit. As the generator load increases, the PCM will adjust the idle speed accordingly. If the IP cluster does not see any activity from the PCM the IP Cluster will illuminate the volts telltale lamp.
If the voltage telltale is on and the (L) terminal voltage is low while the PCM is commanding the generator on for more than 30 seconds OR
If the voltage telltale is on and the PWM is less than 5 percent while engine RPM is less than 2500 for more than 30 seconds DTC P0620 will set.
The low battery message may not appear if other messages are being commanded, such as the rear compartment lid open, driver or passenger doors ajar. Ensure that all doors and compartment lids are completely closed. If the voltage telltale is on but no DTCs are set, use the A Diagnostic System Check - Starting and Charging in Engine Electrical, and the A Diagnostic System Check - Instrument Cluster, or A Diagnostic System Check - Driver Information Systems in Instrument Panel, Gauges, and Console to diagnose the condition.
GENERATOR ASSEMBLY
The generator assembly is mounted to the front of the engine on the passenger side of the vehicle. The CS-type generator uses an internal regulator which features built-in fault detection. The generator used on this vehicle, is not to be disassembled for service. Refer to the table below to identify the generator and specifications.
For more information regarding the Charging System, refer to Charging System Description, and Charging System Circuit Description in Starting and Charging.