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: 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 | Reference |
|---|---|---|---|---|
| Fog lamp relay | Fog lamp request signal | BCM (CAN) | Fog lamp (if equipped) | OPERATION |
|
|
BCM (CAN) |
|
SYSTEM |
| Tail lamp relay | Position light request signal | BCM (CAN) |
|
HAZARD LAMP OPERATION |
|
Front wiper request signal | BCM (CAN) | Front wiper motor | SYSTEM |
| Front wiper stop position signal | Front wiper motor | |||
| Rear window defogger relay | Rear window defogger relay control signal | BCM (CAN) | Rear window defogger | SYSTEM |
| Starter control relay | Starter control relay signal | BCM (CAN) | Starter motor | SYSTEM |
| Transmission range switch signal (CVT models) | Transmission range switch | |||
| Clutch interlock switch signal (M/T models) | Clutch interlock switch | |||
|
Cooling fan speed request signal | ECM (CAN) | Cooling fan | SYSTEM DESCRIPTION |
| A/C relay | A/C compressor request signal | ECM (CAN) | A/C compressor (Magnet clutch) | AIR OUTLET CONTROL
(automatic air conditioner) AIR FLOW CONTROL (manual air conditioner) |
| ECM relay | ECM relay control signal | ECM (CAN) | ECM | SYSTEM |
| Throttle control motor relay | Throttle control motor control signal | ECM (CAN) | ECM | P2119 ELECTRIC THROTTLE CONTROL ACTUATOR |
| Fuel pump relay | Fuel pump request signal | ECM (CAN) | Fuel pump | FUEL PUMP |
| Ignition relay-1 | Ignition switch ON signal | BCM (CAN) | Each control unit, sensor, actuator and relay (Ignition power supply) | SYSTEM |
| Vehicle speed signal (Meter) | Combination meter (CAN) | |||
| Push-button ignition switch signal | Push-button ignition switch |
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.
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