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
Service Data
SERVICE BATTERY DATA
| Battery | Voltage (Maintenance-free battery): at 20°C (68°F) | 12.5 - 12.9 V | |
| Specific gravity (Except maintenance-free battery): at 20°C (68°F) | 1.25 - 1.29 | ||
| Alternator | Rated output | 12 V 80 A | |
| Rotor coil resistance: at 20°C (68°C) | 2.1 - 2.5ohm | ||
| Slip ring diameter | STD | 14.2 - 14.4 mm (0.559 - 0.567 in.) | |
| Minimum | 12.8 mm (0.504 in.) | ||
| Brush exposed length | STD | 9.5 - 11.5 mm (0.374 - 0.453 in.) | |
| Minimum | 1.5 mm (0.059 in.) | ||
| Voltage regulator | Regulating voltage | 13.2 - 14.8 V | |
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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