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.
RELAY CONTROL SYSTEM: System Description
IPDM E/R activates the internal control circuit to perform the relay ON-OFF control according to the input signals from various sensors and the request signals received from control units via CAN communication.
| Control relay | Input/output | Transmit unit | Control part | Refer to | ||
|---|---|---|---|---|---|---|
| Headlamp low relay |
|
BCM (CAN) | Headlamp (LO) |
|
||
| Headlamp high relay | High beam request signal | BCM (CAN) | Headlamp (HI) | |||
| Front fog lamp relay | Front fog light request signal | BCM (CAN) | Front fog lamp | FRONT FOG LAMP SYSTEM | ||
| Tail lamp relay | Position light request signal | BCM (CAN) |
|
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| Illumination | SYSTEM | |||||
|
Front wiper request signal | BCM (CAN) | Front wiper motor | SYSTEM | ||
| Front wiper position signal | Front wiper motor | |||||
|
|
BCM (CAN) |
|
VEHICLE SECURITY SYSTEM | ||
|
Starter control relay signal | BCM (CAN) | Starter motor | |||
| Steering lock unit condition signal | Steering lock unit | |||||
| Starter relay control signal | TCM | |||||
| A/C relay | A/C compressor request signal | ECM (CAN) | A/C compressor (magnet clutch) | AUTOMATIC AIR CONDITIONING SYSTEM: AIR OUTLET CONTROL | ||
| Ignition relay | Ignition switch ON signal | BCM (CAN) | Each control unit, sensor, actuator and relay (ignition power supply) | SYSTEM DESCRIPTION | ||
| Vehicle speed signal | Combination meter (CAN) | |||||
| Push-button ignition switch signal | Push-button ignition switch | |||||
| Daytime running light relay |
|
BCM (CAN) |
|
AUTO LIGHT SYSTEM (WITH DTRL): SYSTEM DESCRIPTION | ||
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NOTE:
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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.
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