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.
2014 Nissan-Datsun Altima BaseFACTORY OEM SERVICE PROCEDURE
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.
CAUTION:
IPDM E/R integrated relays cannot be removed.
| Control relay | Input/output | Transmit unit | Control part | Reference |
|---|---|---|---|---|
| Front fog lamp relay | Front fog lamp request signal | BCM (CAN) | Front fog lamp | FRONT FOG LAMP CIRCUIT |
| Headlamp high relay | High beam request signal | BCM (CAN) | Headlamp high | HEADLAMP (HI) CIRCUIT |
| Headlamp low relay | Low beam request signal | BCM (CAN) | Headlamp low | HEADLAMP (LO) CIRCUIT
(halogen) HEADLAMP (XENON) (xenon) |
| Tail lamp relay | Position light request signal | BCM (CAN) |
|
PARKING LAMP CIRCUIT |
|
Front wiper request signal | BCM (CAN) | Front wiper | FRONT WIPER DOES NOT OPERATE |
| Front wiper auto stop signal | Front wiper motor | |||
| Cooling fan relay-1 | Cooling fan request signal | ECM | Cooling fan | COOLING FAN
(QR25DE) COOLING FAN (VQ35DE) |
| A/C relay | A/C compressor request signal | ECM (CAN) | A/C compressor | MAGNET CLUTCH
(automatic air conditioner) MAGNET CLUTCH (manual air conditioner) |
| Ignition relay-1 | Ignition switch ON signal | BCM (CAN) | Ignition relay-1 | B260A IGNITION RELAY |
| Vehicle speed signal | Combination meter (CAN) | |||
| Push-button ignition switch | Push-button ignition switch | |||
| Fuel pump relay | Fuel pump request signal | ECM | Fuel pump | FUEL PUMP
(QR25DE) FUEL PUMP (VQ35DE) |
| ECM relay | ECM relay control signal | ECM | ECM relay | POWER SUPPLY AND GROUND CIRCUIT
(QR25DE) POWER SUPPLY AND GROUND CIRCUIT (VQ35DE) |
| Throttle control motor relay | Throttle control motor relay signal | ECM | Throttle control motor relay | P2101 ELECTRIC THROTTLE CONTROL FUNCTION
(QR25DE) P2101 ELECTRIC THROTTLE CONTROL FUNCTION (VQ35DE) |
| Starter relay | Starter relay control signal | BCM | Starter motor | IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM) |
| Starter control relay |
Factory Service Tools
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.