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.
2004 Infiniti Q45FACTORY OEM SERVICE PROCEDURE
Control Units
CONTROL UNITS LOCATION
| Component | Location |
|---|---|
| A/C Auto Amp. | Behind right side of dash.Figure . |
| Accessory Relay | On back of fuse block (J/B) No. 1.Figure . |
| Active Damper Suspension Control Unit | Behind left rear shock tower.Figure . |
| Air Bag Diagnosis Sensor Unit | Under rear of center console.Figure . |
| ASCD Control Unit | Behind dash, left of steering column.Figure . |
| Auto Trunk Control Unit | At rear of luggage compartment.Figure . |
| AV Control Unit | Behind center of dash.Figure . |
| AV & NAVI Control Unit (W/NAVI) | Under left side of rear parcel shelf.Figure . |
| BCM | Behind left kick panel. See.Figure . |
| (Daytime Light Control Unit (Canada) | Left side of engine compartment.Figure . |
| Door Mirror Defogger Relay | On fuse block (J/B) No.1.Figure . |
| Driver Door Control Unit (D8) | In driver's door. See Figure . |
| Driver Side Door Mirror Control Unit (D5) | In driver's door. See Figure . |
| Driver Seat Control Unit | Under driver's seat.Figure . |
| Dual Mode Muffler Control Unit | At right side of trunk. See.Figure . |
| ECM | Behind glove box.Figure . |
| Fuel Level Sensor & Fuel Pump (B239) | At fuel tank. See Figure . |
| Fuel Pump Control Module | At right side of trunk.Figure . |
| Headlamp Battery Saver Control Unit | Behind dash, left of steering column.Figure . |
| ICC Unit | At right side of trunk.Figure . |
| Left Side Curtain Air Bag Module (B24) | At left "B" pillar. See Figure . |
| Low Tire Pressure Warning Control Unit | Behind center of dash.Figure . |
| NATS IMMU | Behind dash, left of steering column.Figure . |
| Passenger Door Control Unit | In front passenger's door. See Figure . |
| Passenger Side Door Mirror Control Unit | In front passenger's door. See Figure . |
| Power Steering Control Unit | Behind dash, right side of center console. See.Figure . |
| Rear LH Door Control Unit (D58) | In left rear door.Figure . |
| Rear Power Seat Control Unit (LH) | Under left rear seat. See Figure . |
| Rear Power Seat Control Unit (RH) | Under right rear seat.Figure . |
| Rear RH Door Control Unit | In right rear door. See Figure . |
| Rear Sunshade Unit | At right "C" pillar.Figure . |
| Rear View Camera Control Unit | At center front of trunk.Figure . |
| Right Side Curtain Air Bag Module (B224) | At right "C" pillar. See Figure . |
| Shift Lock Control Unit | Behind dash, left of steering column.Figure . |
| Steering Lock Control Unit | Behind dash, right of steering column.Figure . |
| TCM (Transmission Control Module) | Behind glove box.Figure . |
| Trunk Closure Control Unit | At center rear of trunk.Figure . |
| Trunk Lid Opener Relay | On back of fuse block (J/B) No.1.Figure . |
| VDC/TCS/ABS Control Unit | Behind right kick panel. See.Figure . |
| Voice Activated Control Module | Left rear of trunk.Figure . |
Factory Service Tools
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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.