Step  | Action  | Values  | Yes  | No  | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1  | Inspect for a loss of system pressure and/or coolant. Is there a loss of system pressure and/or coolant?  | --  | Go to Step 2  | Go to Step 3  | ||||||||||
2  | Inspect and repair any faulty hose connections or radiator cap. Fill the system to the proper level, then retest. Does the engine still overheat beyond the specified value?  | 125°C (257°F)  | Go to Step 3  | System OK  | ||||||||||
3  | Inspect the coolant concentration for low temperature protection below the specified value. Is the proper low temperature protection present?  | -37°C (-34°F)  | Go to Step 5  | Go to Step 4  | ||||||||||
4  | Replace the coolant. Refer to Cooling System Draining and Filling . Does the engine still overheat?  | --  | Go to Step 5  | System OK  | ||||||||||
5  | Inspect the drive belt for excessive wear or low tension. Is the drive belt worn or is the tension too low?  | --  | Go to Step 6  | Go to Step 7  | ||||||||||
6  | Replace the drive belt. Refer to Drive Belt Replacement . Does the engine still overheat?  | --  | Go to Step 7  | System OK  | ||||||||||
7  | Inspect the radiator fins for obstruction. Are the radiator fins obstructed?  | --  | Go to Step 8  | Go to Step 9  | ||||||||||
8  | Inspect and clean the radiator. Refer to Radiator Cleaning . Does the engine still overheat?  | --  | Go to Step 9  | System OK  | ||||||||||
9  | Inspect the water pump for physical damage. Is the water pump damaged or inoperative?  | --  | Go to Step 10  | Go to Step 11  | ||||||||||
10  | Replace the water pump. Refer to Water Pump Replacement . Does the engine still overheat?  | --  | Go to Step 11  | System OK  | ||||||||||
11  | Inspect the cooling system passages for obstruction. Is the cooling system passage blocked?  | --  | Go to Step 12  | Go to Step 13  | ||||||||||
12  | Inspect and flush the system. Refer to Flushing . Does the engine still overheat?  | --  | Go to Step 13  | System OK  | ||||||||||
13  | Inspect the electro-viscous fan. Is the electro-viscous fan inoperative?  | --  | Go to Step 14  | Go to Step 15  | ||||||||||
14  | Replace the electro-viscous fan. Does the engine still overheat?  | --  | Go to Step 15  | System OK  | ||||||||||
15  | Inspect for a stuck thermostat. Refer to Thermostat Diagnosis . Is the thermostat stuck in the closed position?  | --  | Go to Step 16  | Go to Step 17  | ||||||||||
16  | Replace the thermostat. Refer to Engine Coolant Thermostat Replacement . Does the engine still overheat?  | --  | Go to Step 17  | System OK  | ||||||||||
17  | The following factors may cause the engine to overheat: 
 
 
 
 
 Correct or repair as necessary. Does the engine still overheat?  | --  | --  | System OK  |