Alternator (FA20): Inspection

Inspection of light-emitting diode

Check the continuity between the light-emitting diode lead and terminal E or terminal B. Replace the rectifier if the continuity is not as shown in the table.

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TESTER LEAD DESCRIPTION - ANALOG TESTER

Tester lead		Conductor
- Lead	+ Lead	Conductor
E	P1, P2, P3, P4, P5, P6	ON
B	P1, P2, P3, P4, P5, P6	None
P1, P2, P3, P4, P5, P6	E	None
P1, P2, P3, P4, P5, P6	B	ON

TESTER LEAD DESCRIPTION - DIGITAL TESTER

Tester lead		Conductor
- Lead	+ Lead	Conductor
E	P1, P2, P3, P4, P5, P6	None
B	P1, P2, P3, P4, P5, P6	ON
P1, P2, P3, P4, P5, P6	E	ON
P1, P2, P3, P4, P5, P6	B	None

CAUTION: Megger testers (used for measuring high voltage) or other equivalent measuring instruments may damage the light-emitting diode. Do not use such instruments for this test.

Brush check

Using a vernier caliper, measure the brush length.

Standard length: 22.5 mm {0.885 in}

Minimum length: 5.0 mm {0.196 in}

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If the brush length is less than the minimum, replace the brush.

Check the brush spring for appropriate pressure. Insert the brush to the brush holder until its tip comes out from the brush holder by 2 mm (0.0787 in.). Then, use the spring pressure indicator to measure the brush spring pressure. Replace the brush spring if the pressure is 1.7 N (173 gf, 6.11 ozf) or less. The pressure of a new spring must be 4.1 - 5.3 N (418 - 540 gf, 14.75 - 19.06 ozf).

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