BELT-SERPENTINE 3493353 - Caterpillar

Diagnosis Procedure
If equipped with electric start, do not crank the engine for more than 30 seconds. Allow the starter to cool for two minutes before cranking again.Never turn the disconnect switch off while the engine is running. Serious damage to the electrical system can result.
If electric starting motor (10) does not crank or cranks slow, perform the following procedure:
Measure the voltage of battery (14) at the battery posts with the multimeter when you are cranking the engine or attempting to crank the engine. Measure the voltage across the battery posts. Do not measure the voltage across the cable post clamps.
Battery voltage
Go to Step 3 if the voltage is equal to the voltage that is given in Table 2 or if the voltage is greater than the voltage that is given in Table 2.
The battery voltage is less than the voltage in Table 2.Refer to Special Instruction, SEHS7633 in order to test battery (14) .A low charge in a battery can be caused by several conditions.
Deterioration of the battery
A shorted starting motor
A faulty alternator
Loose drive belts
Current leakage in another part of the electrical system
Measure the current from the positive "+" battery terminal to starting motor solenoid (9) . Use the 225-8266 Ammeter Tool Gp . The maximum current that is allowed for no load conditions is given in the Specifications module, "Electric Starting Motor" topic.Note: If the following conditions exist, do not perform the test in Step 3 because electric starting motor (10) has a problem.
The voltage at the battery post is within 2 V of the lowest value in the applicable temperature range of Table 2.
The large starting motor cables get hot.The current and the voltages that are specified in the Specifications Module, "Electric Starting Motor" are measured at a temperature of 27 °C (80 °F). When the temperature is below 27 °C (80 °F), the voltage will be less than the values that are specified. Also, the current through electric starting motor (10) will be higher. If the current is too great, a problem exists in electric starting motor (10) . Repair the problem or replace electric starting motor (10) .
Measure the voltage from point "MTR" to the ground connection of electric starting motor (10) . Use the multimeter when you are cranking or attempting to crank the engine. Refer to Illustration 2.
Voltage between electric starting motor (10) from "MTR" to the ground connection of electric starting motor (10)
The voltage is equal to the voltage that is given in Table 2 or the voltage is greater than the voltage that is given in Table 2.The battery and the electric starting motor cables to electric starting motor (10) are within specifications. Go to Step 8.
The electric starting motor voltage is less than the voltage specified in Table 2.The voltage drop between battery (14) and electric starting motor (10) is too great. Go to Step 6.
Measure the voltage