Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Is the TEMP light on or is the TEMP gauge indicating an overheating condition? | -- | Go to Step 2 | Go to Step 4 |
2 | Check the engine coolant temperature sending unit. Is the sending unit functioning normally? | -- | Go to Step 5 | Go to Step 3 |
3 | Replace the engine coolant temperature sending unit. Is the repair complete? | -- | System OK | -- |
4 | Is the vehicle showing symptoms of an overheat condition? | -- | Go to Step 5 | System OK |
5 | Check the pressure cap. Is the pressure cap operating correctly? | -- | Go to Step 6 | Go to Step 7 |
6 | Replace the pressure cap. Is the repair complete? | -- | Go to Step 7 | -- |
7 | Check the coolant level. Is the coolant level OK? | -- | Go to Step 8 | Go to Cooling System Diagnosis |
8 | Is the TEMP light on or is the TEMP gauge indicating an overheating condition? | -- | Go to Step 9 | Go to Step 18 |
9 | Perform an on-vehicle thermostat check. Refer to Thermostat Diagnosis. Is the action complete? | -- | Go to Step 10 | -- |
10 | Check the engine drive belt. Is the drive belt tight and in good condition? | -- | Go to Step 12 | Go to Step 11 |
11 | Replace the drive belt or the drive belt tensioner. Is the repair complete? | -- | Go to Step 12 | -- |
12 | Check the upper and lower radiator hoses for signs of collapse, splits, cracks, etc. Are the hoses OK? | -- | Go to Step 14 | Go to Step 13 |
13 | Replace the worn hoses. Is the repair complete? | -- | Go to Step 14 | -- |
14 |
Are the radiator and the aftercooler/oil cooler OK? | -- | Go to Step 16 | Go to Step 15 |
15 | Clean or straighten the cooling fins on the radiator, aftercooler or oil cooler. Are the cooling fins straight and free of dirt and debris? | -- | Go to Step 16 | -- |
16 | Is the vehicle still showing symptoms of an overheat condition? | -- | Go to Step 17 | System OK |
17 |
Have all the steps been completed? | -- | Go to Uncommon Cooling System Problems | Go to Step 1 |
18 | Check the TEMP bulb. Is the TEMP bulb working? | -- | Go to Step 20 | Go to Step 19 |
19 | Replace the bulb. Is the repair complete? | -- | Go to Step 9 | -- |
20 | Check the anti-freeze protection level. Does the anti-freeze protect according to specifications? | -- | Go to Step 22 | Go to Step 21 |
21 | Add coolant or flush the cooling system in order to bring the coolant up to specifications. Is the action complete? | -- | Go to Step 9 | -- |
22 | Check the engine coolant temperature sending unit. Is the sending unit functioning normally? | -- | Go to Step 9 | Go to Step 23 |
23 | Replace the engine coolant temperature sending unit. Is the repair complete? | -- | Go to Step 9 | -- |
