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 Lexus IS 300 Base, AutomaticFACTORY OEM SERVICE PROCEDURE
Electrical Component Locator: Splices
SPLICES LOCATION
| Component | Component Location |
|---|---|
| B1 | In body harness, at center of headliner. |
| B2 | In body harness, at center of headliner. |
| B3 | In body harness, behind left rear wheelwell. |
| B4 | In body harness, behind left rear wheelwell. |
| B5 | In body harness, under left front seat. |
| B6 | In body harness, under right front seat. |
| E1 | In engine harness, at right front of engine compartment. See Figure. |
| E2 | In engine harness, at left front of engine compartment. See Figure. |
| E3 | In engine harness, at left front of engine compartment. See Figure. |
| E4 | In engine harness, at left front of engine compartment. See Figure. |
| E5 | In engine harness, at top left side of engine. See Figure. |
| E6 | In engine harness, at top left side of engine. See Figure. |
| E7 | In engine harness, at top left side of engine. See Figure. |
| E8 | In engine harness, at top left side of engine. See Figure. |
| E9 | In engine harness, at top left side of engine. See Figure. |
| E10 | In engine harness, at top left side of engine. See Figure. |
| E11 | In engine harness, at top left side of ECU box. See Figure. |
| I1 | In dash harness, behind left side of dash. See Figure. |
| I2 | In dash harness, behind left side of dash. See Figure. |
| I3 | In dash harness, behind left side of dash. See Figure. |
| I4 | In dash harness, at top center of dash. See Figure. |
| I5 | In dash harness, behind right side of dash. See Figure. |
| I6 | In dash harness, behind left side of dash. See Figure. |
| I7 | In dash harness, behind left side of dash. See Figure. |
| I8 | In dash harness, behind lower left corner of instrument panel. See Figure. |
| I9 | In dash harness, behind top center of dash. See Figure. |
| I10 | Behind right side of dash. See 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.
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