DEFINITION: The cooling system is loosing coolant either internally or externally.

Inspect the coolant level.

Is the coolant at the proper level?

Go to Step 13

Go to Step 2

Fill the cooling system to the proper level. Refer to Generator Control Module Cooling System Draining and Filling.

Is the action complete?

Go to Step 3

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Overheating can cause a loss of coolant.

Is the Hybrid Cooling system overheating?

Go to Step 11

Go to Step 4

Visually inspect the hoses, pipes and hose clamps.

Are any of the hoses, clamps or pipes leaking?

Go to Step 12

Go to Step 5

Visually inspect the following components:

Are any of the listed components leaking?

Go to Step 12

Go to Step 6

1. Pressure test the cooling system. Refer to Hybrid Cooling System Leak Test.
2. With the cooling system pressurized, visually inspect the components listed in step 5.

Are any leaks present?

Go to Step 12

Go to Step 7

Pressure test the coolant pressure cap. Refer to Hybrid Cooling System Pressure Cap Testing.

Does the coolant pressure cap hold pressure?

Go to Step 9

Go to Step 8

Replace the coolant pressure cap.

Is the repair complete?

Go to Step 13

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1. Pressure test the cooling system. Refer to Hybrid Cooling System Leak Test.
2. With the cooling system pressurized, remove the engine cooling system pressure cap.

Does the hybrid cooling system hold pressure?

--

Go to Step 10

Replace the surge tank. Refer to Radiator Surge Tank Replacement.

Is the repair complete?

Go to Step 13

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Repair the hybrid cooling system overheating condition. Refer to Hybrid Cooling System Overheating.

Is the repair complete?

Go to Step 13

--

Repair or replace the leaking component. Refer to the appropriate repair.

Is the repair complete?

Go to Step 13

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Operate the system in order to verify the repair.

Did you find and correct the condition?

System OK

Go to Step 2