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.

2000 Infiniti Q45 BaseFACTORY OEM SERVICE PROCEDURE

Retrieving Diagnostic Trouble Codes Using Mil (Q45 Only): Notes

NOTE: CHECK ENGINE or SERVICE ENGINE SOON light is now referred to as Malfunction Indicator Light (MIL).

Turn ignition on. Verify MIL is properly illuminated. If MIL does not illuminate, repair MIL circuit. See WIRING DIAGRAMS article. Turn mode selector switch on ECM fully clockwise. MIL should turn off. Wait 2 seconds, and turn mode selector fully counterclockwise. System is now in Diagnostic Test Mode II. Retrieve Diagnostic Trouble Codes (DTCs) by observing MIL, and counting the number of flashes. Record all codes set and then go to appropriate test procedure. MIL DTC numbering is different than CONSULT or scan DTC numbering. See DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION (Q45) table.

Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.

Shop Manual-Ready Tools Compare Repair Quote Quote Shield Pro

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.