Alternator field terminals both read full voltage when. Pcm operation two different control modules are used. I believe 12v is supplied to the powertrain control module pcm from two sources a relay and the ignition switch. If it asd relay wasnt working it wouldnt even start. Intelligent charging for the vehicle electrical system. If the voltage differs by some amount this code is set. General motors cs series generators may be connected directly to the pcm through terminals l and f at the generator. The generator regulates the field using pin1 of the field connector high side driver. When generator operation is desired, the pcm sends a 5 volt signal to the voltage regulator via the generator turn on signal circuit. Apr 06, 2015 this is a computer controlled alternator. Measure the voltage on the k20 gen field control circuit in the generator field harness connector.
Alternator voltage regulator with load response control. If you look at your alternator youll see the field coil windings inside the case through the cooling vents. Pin 86 light greenblack startrun feed from the ignition switch and fuse 9. I will be walking you through the steps involved in making sure the wiring is correct. Generator control idling stability has been improved by optimum control of generator voltage according to engine operation and electrical load conditions. If the exciter field winding is shorted or not functioning because. The generator field duty cycle signal circuit connects to high side of the field windings in the generator. Alternatorfield duty signal wirepcm problem gmtnation. Pin 10 on pcm connector c2 and pin 25 on pcm connector c3 form the source for the field winding. The pcm determines the engine operation and electrical load conditions based on the input signals from each control part and controls the energization time of the generator field coils. When driving, you might find that shifting is a challenge. Field duty middle plugpin51both the red and grey wires tested fine for continuity to the pinholes on cabling.
As you can see they have had issues with the circutry from the generator to the pcm. How to bypass the generator battery control module. The user can configure the pcm format to be generated. Also, tested for shorts and could not find any on both grey and red wires. This allow the pcm to adjust the idle speed to compensate for high electrical loads. Jan 01, 2016 using scan tool, actuate generator field driver circuit. The pcm monitors the status of the generator field duty cycle signal. Hyundai p0620 generator control circuit malfunction car. Dodge dakota warning lights and trouble codes page 3 car. The generator field duty cycle signal circuit connects to the high side of the field winding in the generator.
A circuit in the pcm cycles the ground side of the generator field at 250 times per second 250hz, but has the capability to ground the field control wire 100% of the time full field to achieve the target voltage. The powertrain control module pcm, and the engine control module ecm. Dodge dakota warning lights and trouble codes page 3. Calculates the optimum target throttle valve opening angle and controls the throttle valve actuator which allows the driver to drive the vehicle at will. The powertrain control module pcm uses the generator turn on signal circuit to control the generator. In addition, some vehicles use a generator field duty cycle signal input to the pcm to monitor the duty cycle onoff of the generator. If the charging rate cannot be monitored limpin, a duty cycle of 25% is used by the pcm in order to have some generator output. The computer controls outputs like the injectors, fans, solenoids, and relays to operate the various components.
Jan 20, 2016 pcm operation two different control modules are used. A pulse widht modulated pwm high side driver in the voltage regulator turns the field warnings on and off. The pcm also adjusts the generator charge rate through control of the generator field and provides speed control operation. P1638 cadillac generator f terminal circuit conditions. How to test an alternator chrysler dodge jeep youtube.
If voltage is greater than 10 volts, go to next step. Cam,crank,fuel injectors,ignition coil pack,alternator. The processor in the ecm uses the information to make decisions. Operation the amount of dc current produced by the generator is controlled by evr. The pcm monitors the continuity and voltage level of the. Using test light connected to ground, backprobe terminal no. A stored code p0622 means that the powertrain control module pcm has detected a malfunction with the generator field coil control circuit. The two technologies dis cussed allow for a bidirectional. The powertrain control module pcm uses the generator field duty cycle signal circuit to monitor the duty cycle of the generator. Jun 23, 2011 generator field driver circuit shorted to ground daniel.
Disconnect the generator field harness connector at back of the generator. Repair the open in the z1 gen field ground circuit. Obd code p0622refers to the pcm monitors generator load from the generator regulator in the form of frequency. Generator load on the engine is calculated based on a pwm signal from the generator.
A pulse widht modulated pwm high side driver in the voltage regulator turns the field windings on and off. Measure the generator field driver circuit from pcm to generator. This voltage is connected through the pcm and supplied to one of the generator field terminals gen. Jan 06, 2014 how to test an alternator testing the voltage regulator, diode rectifier and stator duration. The generator is internally grounded and regulates the field using pin1 of the field connector high side driver. The powertrain control module pcm uses a generator field duty cycle signal to monitor the duty cycle of the generator. P0622 generator field not switching properly obdii error. P0622 code definition this code is defined as the generator field f control circuit malfunctioning. The ecm directly controls the generator field control circuit input to the generator.
What the p0622 code means when the pcm powertrain control module logs a. The device regulates the output of an automotive generator by controlling the field winding current. I will be walking you through the steps involved in. If voltage is 10 volts or less, repair open or high resistance in dark blue wire between generator and terminal no. The f simply reiterates the field coil control circuit is at fault. This circuit ties the ignition switch to the powertrain control module pcm. This system is an independent unit with lcd and keypad for user interface. Intrepid stalls when alternator connected dodgeintrepid. Evr circuitry is connected in series with the generator field driver terminal and ground.
P0622 alternator, field control circuit malfunction troublecodes. Ecm not communicating with alternators voltage regulator. Repair the open in the k20 generator field control circuit. The field coil surrounds the generator armature and remains stationary in the alternator housing. Pin 10 is the generator field driver and pin 25 is the the generator field source on the autozone bench, the alternator is placed on a machine that simulates. A circuit in the pcm cycles the ground side of the generator field up to 250 times per second 250hz, but has the capability to ground the field control wire 100% of the time full field to achieve the target voltage. On modern applications, the pcm uses a dedicated alternator field duty cycle.
Two different powertrain control module pcm 5volt supply circuits are used. Thats the ground signal from the pcm to operate the asd relay. The field coil is probably most recognizable from its windings which are visible through the vent holes on most alternators. The second terminal is labeled b, sense or kelvin sense, and used by the pcm to monitor charging voltage.
The engine computer system referred to as an engine control module ecm, or powertrain control module pcm uses a variety of input sensors and switches for information. A circuit in the pcm cycles the ground side of the generator field up to 100 times per second 100hz, but has the capability to ground the field control wire 100% of the time full field to achieve the target voltage. P1638 buick generator f terminal circuit conditions. Based on inputs that it receives, the pcm adjusts ignition coil dwell. Charging system issue the chrysler minivan fan club forums.
Jan 06, 2015 decided to check shortscontinuity at pcm cabling. Voltage regulator in pcm fried dodge ram forum dodge. Jul 18, 2017 the generator field duty cycle signal circuit connects to high side of the field windings in the generator. The field voltage to charge the battery is set by the pcm. This causes the voltage regulator to begin controlling the generator field circuit. This transistor grounds the ac generators field to control output voltage. P0626 relates to generator fieldf terminal circuit high. Apr 03, 2012 the field voltage to charge the battery is set by the pcm. Generator field driver circuit shorted to ground daniel. The amount of amperage produced by the generator is controlled by electronic voltage regulator evr circuitry within the pcm. The ecm in some manner controls the voltage regulator, which charges the battery. The voltage regulator portion of the pcm switches the field current on and off at a. The pcm monitors the continuity and voltage level of the generator field control circuit whenever the engine is running. Function of generator field duty cycle signal on pcm fixya.
The voltage regulator portion of the pcm switches the field current on and off at a frequency of about 400 times per second. A high side driver within the pcm allows the pcm to turn the generator on and off. The engine is a 2008 cadillac lc3 using an e67 pcm and the. This lead controls power to the generator field, fuel injectors, and oxygen sensor heaters. P0622 generator field f control circuit malfunction obd codes. A battery temperature sensor bts, located in battery tray, is used to sense battery temperature. If the charging rate cannot be monitored limpin, a duty cycle of 25% is used by the pcm in order to have some generator.
Gen iii pcms have the ability to control generator load on the engine through a turnon signal output. How to test an alternator testing the voltage regulator, diode rectifier and stator duration. Pulse code modulation generators for telemetry equipment pcm generator the pcm generator system used to generate different types of pcm format signals. Using an external ohmmeter, check for resistance in field driver circuit alternator harness terminal and cavity no. The pcm uses the pwm signal input to determine the generator load on the engine. A pulse width modulated pwm high side driver in the voltage regulator turns the field winding on and off. When generator operation is desired, the pcm sends a 5 volt signal to the voltage regulator via.
487 594 1200 815 1023 897 1188 1618 1060 148 1174 1559 297 1267 1062 380 1153 1234 742 1433 682 444 579 572 1624 1260 507 568 74 10 618 583 587 1440 1459 1004 1346 700 332 493 29 697 1376 549