BEZEL 4804184 - Caterpillar

Illustration 1 g01276092Specification
This test measures a voltage drop of either polarity across the alternator circuit breaker. The voltage drop is measured across test point 1 and test point 9.A voltage drop will cause the indicator lamp for the lamp for the alternator circuit breaker to turn ON. The voltage drop must be larger than 0.45 0.15 volts. The lamp turned ON in order to indicate a defect in the circuit. A defect can be indicated during any Test Step.The possible causes of this condition are listed:
Activated breaker
Closed breaker with excessive voltage dropInformation for Other Circuits
In the steps "Test Setup A, Hookup", "Test Step B, Crank", and "Test Step C, Start Aid" test point (1) will be positive and test point (9) will be negative. Test point (1) and test point (9) are this way because the battery is sourcing current through the alternator circuit breaker (D) to the circuits for cranking.The voltage will reverse polarity at test point (1) and test point (9) during "Test Step D, High Idle". Test point (1) will be negative and test point (9) will be positive. The polarity reverses because the battery is receiving current through alternator circuit breaker (D) from alternator circuit breaker (H).The batteries cannot get a full charge if the charging circuit has an excessive voltage drop.The indicator for the alternator circuit breaker blinks for a few seconds. The indicator may turn ON for a few seconds. The indicator will turn OFF and the indicator for the alternator will turn ON. This is acceptable during engine start-up.