Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Input Devices: Generator
Generator output is controlled by PCM based on battery voltage input and ambient temperature. PCM keeps charging system output voltage at 12.9-15.0 volts. Charging system output voltage is controlled by generator voltage regulator (field control), located within PCM. The voltage determined by PCM as final goal for charging system is called "control" voltage. The control voltage will be used to determine generator field control and to detect if charging system is operating properly.
If sensed voltage is lower than "control" voltage, PCM will alter duty cycle and ground generator (rotor) field for a longer period of time and create a higher generator output which should raise sensed voltage level. If sensed voltage is higher than "control" voltage, PCM will alter duty cycle and lower generator output, which should lower sensed voltage level.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.