Alternator: Testing and Inspection

1UR-FE BATTERY / CHARGING: GENERATOR: INSPECTION

1. INSPECT GENERATOR ROTOR ASSEMBLY

(a) Check the generator rotor for an open circuit.

(1) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

for 130 A Type





for 150 A Type









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If the result is not as specified, replace the generator rotor assembly.

(b) Check if the generator rotor is grounded.

(1) Measure the resistance according to the value(s) in the table below.

Standard Resistance:









Text in Illustration





If the result is not as specified, replace the generator rotor assembly.

(c) Using a vernier caliper, measure the slip ring diameter.

Standard diameter:

14.2 to 14.4 mm (0.559 to 0.567 in.)

Minimum diameter:

14.0 mm (0.551 in.)





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If the diameter is less than the minimum, replace the generator rotor assembly.

(d) Check that the generator rotor bearing is not rough or worn.





If necessary, replace the generator rotor assembly.

2. INSPECT GENERATOR BRUSH HOLDER ASSEMBLY

(a) Using a vernier caliper, measure the brush length.

Standard exposed length:

9.5 to 11.5 mm (0.374 to 0.453 in.)

Minimum exposed length:

4.5 mm (0.177 in.)





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If the brush length is less than the minimum, replace the generator brush holder assembly.