METER GP-VOLT 1187862 - Caterpillar

Illustration 1 g01276763Specification
This test measures the voltage drop across the coolant switch. The voltage drop is measured across test point (11) and test point (7). Test point (11) is the positive contact and test point (7) is the negative contact.A voltage drop will cause the indicator lamp for the coolant to turn ON. The voltage drop must be larger than 1.30 0.15 volts. The lamp turned ON in order to indicate a defect.The possible causes of this condition are listed:
Open switch
Closed switch with excessive voltage drop
Switch with welded contactsInformation for Other Circuits
The coolant switch opens when the engine coolant temperature reaches 38°C (100°F).This switch prevents the use of a starting aid in a warm engine. The use of a starting aid in a warm engine may cause possible damage.The engine coolant must be below a temperature of 38°C (100°F) in order for this test to be valid. A warm engine must first cool down to a temperature of 27°C (80°F) in order to close the coolant switch.