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.
2003 Infiniti I35FACTORY OEM SERVICE PROCEDURE
DTC Confirmation Test (Using Generic Scan Tool)
CAUTION:
DO NOT use ECM ground terminals when measuring voltage.
- Start engine and warm to normal operating temperature. Measure voltage between ground and fuel tank temperature sensor signal circuit at ECM terminal No. 75 (Pink/Blue wire) by backprobing. See Figure and Figure . Ensure voltage is less than 4.2 volts.
- Turn ignition off and wait at least 10 seconds. Start engine and wait at least 20 seconds. Select MODE 7 with scan tool. If 1st trip DTC is detected, go to DIAGNOSTIC PROCEDURE . If 1st trip DTC is not detected, system is okay at this time.
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.