Descriptions 2005 Ford F550 Super Duty 6.0L Eng alternator Generator [ DESCRIPTION AND OPERATION ] Generator And Voltage Regulator - 6.0L Diesel The charging system consists of the following components: generator an internal voltage regulator that is not replaced separately generator warning lamp associated wiring The generator and voltage regulator: supply current to the electrical system. charge the battery. adjust the generator field current to increase or decrease the generator output. turn the generator warning lamp on when a problem is detected in the charging system. Generator [ Charging System ] The generator is belt-driven by the engine accessory drive system. The single generator system consists of the generator mounted on the top right of the engine (diesel) or top center of the engine (gas). The gas engines use a 3G 115-amp generator with a 2.71:1 pulley ratio. The 6.0L diesel engine uses a 6G 110-amp generator with a 2.79:1 pulley ratio. The dual generator package consists of an upper/lower dual generator system. The 6.0L upper generator is a VR42 140-amp generator with a 2.79:1 pulley ratio. The 6.0L lower generator is a 4G 120-amp generator with a 3.00:1 pulley ratio. The upper and lower generators are not interchangeable. In the single generator system, with the key in the ON position, voltage is supplied through the instrument cluster warning indicator I circuit to the voltage regulator. The regulator grounds this circuit and the charging system warning indicator is illuminated. When the engine is started, the regulator removes the ground on this circuit and the warning indicator turns off. On the dual generator system, the PCM controls the charging system warning indicator and commands the lamp on if the PCM detects a concern on the monitored circuits. The dual generator system is also monitored and controlled by the PCM. The PCM monitors http://www2.prodemand.com/print/index?content=tabs&module=true&tab=true&terms=true&ymms=false&classname= 1/6
both the upper and lower generator I circuits to determine the output of both generators and sets possible diagnostic trouble codes (DTCs). The PCM controls the lower generator by turning it off when the glow plug system is commanded on by the PCM to avoid possible damage (excessive voltage) to the glow plugs. As soon as the glow plug system stops cycling, the PCM powers up the lower generator. The dual generators operate independently of each other. The control is through the internal voltage regulators. If one generator fails, the other generator can maintain system performance under light load conditions. Under a heavy load, the PCM detects a concern, sets a DTC, and illuminates the warning indicator. The set voltage varies with temperature and is typically higher in cold temperatures than in warm temperatures. This allows for better battery recharge in the winter and reduces the chance of overcharging in the summer. Principles Of Operation [ Charging System - Single Generator ] CONNECTOR C102A END VIEW AND C102B SIDE VIEW TERMINALS (GASOLINE ENGINES) I Circuit 904 (LG/RD) S Circuit 4 (WH/BK) CONNECTOR C102A END VIEW TERMINALS (DIESEL ENGINES) http://www2.prodemand.com/print/index?content=tabs&module=true&tab=true&terms=true&ymms=false&classname= 2/6
Functionality I Circuit 904 (LG/RD) In the single generator system, with the key in the ON position, voltage is applied through the warning indicator I circuit to the voltage regulator. This turns the regulator on, allowing current to flow from battery sense A circuit to the generator field coil. When the engine is started, the generator begins to generate alternating current (AC) which is internally converted to direct current (DC). This current is then supplied to the electrical system through the output terminal (B+) of the generator. Once the generator begins generating current, a voltage signal is taken from the generator stator and fed back to the regulator through the stator circuit 4 (WH/BK). This voltage feedback signal (typically one-half of the battery voltage) is used to turn off the warning indicator on the single generator system. The gas engines have an external stator circuit and the diesel engines have an internal stator circuit. With the system functioning normally, the generator output current is determined by the voltage of the A circuit. This A circuit voltage (battery sense circuit) is compared to a set voltage internal to the regulator, and the regulator controls the generator field current to maintain correct generator output. The set voltage varies with temperature and is typically higher in cold temperatures than in warm temperatures. This allows for better battery recharge in the winter and reduces the chance of overcharging in the summer. The single generator system consists of the generator mounted on the top right of the engine (diesel) or top center of the engine (gas). The gas engines use a 3G 115-amp generator with a 2.71:1 pulley ratio. The 6.0L diesel engine uses a 6G 110-amp generator with a 2:79 pulley ratio. I Circuit - Single Generator The I (ignition) circuit is used to turn on the voltage regulator. This circuit is powered up when the key is in the ON position. Voltage is supplied from the ignition switch to the central junction http://www2.prodemand.com/print/index?content=tabs&module=true&tab=true&terms=true&ymms=false&classname= 3/6
box (CJB) fuse 45 (10A), then to the instrument cluster and through the charge warning indicator (battery icon) to the generator. This circuit is also used to turn the charging system warning indicator on if there is a fault in the charging system operation. S Circuit 4 (WH/BK) The S (stator) circuit 4 (WH/BK) is used to feed back a voltage signal externally from the generator stator to the regulator. This voltage feedback signal (typically half the battery voltage) is used by the regulator to turn off the charging system warning indicator. The gas engines have an external stator circuit and the diesel engines have an internal stator circuit. The A circuit or battery sense circuit is used to sense battery voltage. This voltage is used by the regulator to determine generator output. This circuit is also used to supply current to the generator field, which determines generator output. Principles Of Operation [ Charging System - Dual Generators ] CONNECTOR C102A END VIEW TERMINALS (DIESEL ENGINE, UPPER GENERATOR) Diesel Engines I Circuit 904 (LG/RD) CONNECTOR C1251A END VIEW TERMINALS (DIESEL ENGINE, LOWER GENERATOR) http://www2.prodemand.com/print/index?content=tabs&module=true&tab=true&terms=true&ymms=false&classname= 4/6
Diesel I A Engines Circuit 1185 (YE) Circuit 35 (OG/LB) Functionality With the key in the ON position (dual generator system), voltage is supplied by the powertrain control module (PCM)-controlled I circuit 1183 (WH/YE) to I circuit 904 (LG/RD) to the upper generator and through the I circuit 1185 (YE) to the lower generator. If the glow plug system is not cycling, the PCM maintains power to the lower generator. If the glow plug system is cycling, the PCM supplies power to the lower generator momentarily to verify there is a volt drop, then shuts off the power on the lower generator I circuit 1185 (YE). Once the glow plug system stops cycling, the PCM supplies power on the lower generator I circuit 1185 (YE), which turns the regulator on allowing current to flow from the battery sense A circuit to the generator field coil, at which time it begins to function normally. The PCM maintains power on the upper generator I circuit 1183 (WH/YE) / 904 (LG/RD), which turns on the regulator, allowing current to flow from the battery sense A circuit to the generator field coil. Once the generator begins generating current, a voltage signal is taken from the generator stator and fed back to the regulator internally. This voltage feedback signal (typically one-half of the battery voltage) is used by the PCM to turn off the warning indicator. With the system functioning normally, the generator output current is determined by the voltage of the A circuit 35 (OG/LB). The A circuit 35 (OG/LB) 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. This allows for more efficient battery recharge in the winter and reduces the chance of overcharging in the summer. I Circuit - Dual Generator The I (ignition) circuit is used to turn on the voltage regulator(s). This circuit is powered up when the key is in the ON position. When the PCM detects key ON, the PCM provides power to the upper generator I circuit 1183 (WH/YE) and also to the lower generator I circuit 1185 (YE). The http://www2.prodemand.com/print/index?content=tabs&module=true&tab=true&terms=true&ymms=false&classname= 5/6
power to the lower generator is only momentary unless the glow plug system is not cycling. Once the glow plugs stop cycling, the PCM provides constant power on the lower generator I circuit 1185 (YE). The A circuit or battery sense circuit is used to sense battery voltage. This voltage is used by the regulator to determine generator output. http://www2.prodemand.com/print/index?content=tabs&module=true&tab=true&terms=true&ymms=false&classname= 6/6