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.
Front Control Module: Operation
As messages are sent over the PCI bus circuit, the front control module reads these messages and controls power to some of the vehicles electrical systems by completing the circuit to ground (low side driver) or completing the circuit to 12 volt power (high side driver). The following functions are Controlled by the Front Control Module:
- Headlamp Power with Voltage Regulation
- Windshield Wiper "ON/OFF" Relay Actuation
- Windshield Wiper "HI/LO" Relay Actuation
- Windshield Washer Pump Motor
- Fog Lamp Relay Actuation
- Park Lamp Relay Actuation
- Horn Relay Actuation
The following inputs are Received/Monitored by the Front Control Module:
- B+ Connection Detection
- Power Ground
- Ambient Temperature Sensing
- Ignition Switch Run
- Washer Fluid Level Switch
- Windshield Wiper Park Switch
- PCI Bus Circuit
Use the Manual With the Right Hardware
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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.