COUPLING 0012038 - Caterpillar

Illustration 1 g01276069Specification
This test measures the terminal voltage of the batteries. The voltage is measured across test point (1) and test point (7).A voltage drop during the "Test Setup A, Hookup" will cause the indicator lamp for the batteries to turn ON. The voltage drop must be below 23.10 0.15 volts. The lamp turned ON in order to indicate a low state of charge.The batteries do not have enough power in order to crank the engine in this condition. A defect can be indicated during any Test Step.The possible causes of this condition are listed:
No alternator output
Worn out batteries that will not hold a charge
Light was left ON while the machine was shut down.Specification
It is normal for the battery voltage to go below 23.1 volts when the engine is cranking. The lamp will turn ON when this happens. The batteries will crank the engine momentarily if the battery voltage goes below 12.50 0.15 volts. The lamp will turn OFF in order to indicate a very low voltage.The possible causes of this condition are listed:
Batteries with low voltage
Faulty starter
Excessive drag of the engine or frictionInformation for Other Circuits
To find the defect that is the cause of problem, check the alternator.No Alternator Output
Jump start the machine in order to check the output of the alternator. For more information, see the explanation of the test in the Systems Operation, "Test Step D, High Idle" section.Check the batteries if the alternator is operating correctly. Charge the batteries if it is necessary. For more information, see the explanation in Special Instruction, SEHS7633, "Battery Test Procedure".Note: See the section on jumping the engine with a booster and starter cables in the OMM for the correct machine.