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 SC 430FACTORY OEM SERVICE PROCEDURE
Armature Test
- Using ohmmeter, check for continuity between all segments of commutator. If continuity does not exist, replace armature. Using ohmmeter, check for continuity between commutator and armature coil core. If continuity exists, replace armature.
- Inspect commutator for dirty or burnt surfaces. Repair as necessary using No. 400 sandpaper or a lathe. Place commutator on "V" blocks. Using a dial gauge, measure circle runout. See STARTER SPECIFICATIONS . Repair as necessary using a lathe.
- Using a vernier caliper, measure commutator diameter. See STARTER SPECIFICATIONS . If commutator diameter is less than minimum specification, replace armature.
- Ensure commutator mica undercut depth is clean and free of foreign materials. Smooth out edge. Measure commutator mica undercut depth. See STARTER SPECIFICATIONS . If undercut depth is less than minimum specification, correct depth by using a hacksaw blade to remove mica from between segments.
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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