Step | Action | Yes | No |
|---|---|---|---|
1 | Inspect for a missing or damaged radiator, upper or lower baffle, and/or radiator air deflector. Is the baffle and/or deflector missing or damaged? | Go to Step 8 | Go to Step 2 |
2 | Inspect for a loss of coolant. Is there a loss of coolant? | Go to Step 3 | Go to Step 4 |
3 | Fill the system to the specified level. Refer to Loss of Coolant . Does the engine overheat? | Go to Step 4 | System OK |
4 | Inspect for low coolant protection. Is the coolant to the correct concentration? | Go to Step 5 | Go to Step 8 |
5 | Inspect for a loss of cooling system pressure. Is there a loss of system pressure? | Go to Step 8 | Go to Step 6 |
6 | Inspect for a faulty engine coolant temperature (ECT) sensor. Refer to DTC P0128 for the 4.4L (LC3) engine, or DTC P0128 for the 4.6L (LH2) engine. Is the sensor operating properly? | Go to Step 7 | Go to Step 8 |
7 | Inspect for a cracked coolant surge tank or a leaking hose. Is the coolant surge tank cracked or is the hose leaking? | Go to Step 8 | Go to Step 3 |
8 | Repair or install new parts as necessary, then retest. Does the engine overheat? | Go to Step 9 | System OK |
9 | Inspect for incorrect drive belt tension. Is the belt tension correct? | Go to Step 10 | Go to Step 8 |
10 |
Is the water pump driveshaft damaged or is the seal leaking? | Go to Step 8 | Go to Step 11 |
11 | Inspect for obstructed radiator air flow or bent radiator fins. Is the radiator air flow obstructed? | Go to Step 8 | Go to Step 12 |
12 | Inspect for blocked cooling system passages. Are the cooling system passages blocked? | Go to Step 8 | Go to Step 13 |
13 | Inspect for inoperative cooling fans. Refer to Cooling Fan Inoperative . Are the cooling fans and the motors operating correctly? | Go to Step 14 | Go to Step 8 |
14 | Inspect the thermostat. Refer to Thermostat Diagnosis . Is the thermostat stuck in the closed position? | Go to Step 15 | Go to Step 16 |
15 | Replace the thermostat. Refer to Engine Coolant Thermostat Replacement . Does the engine overheat? | Go to Step 16 | System OK |
16 | Inspect the radiator cooling capacity. Is the proper sized radiator being used on the vehicle? | Go to Step 3 | Go to Step 17 |
17 | Consult the current parts catalog and replace the radiator. Refer to Radiator Replacement . Is the repair complete? | System OK | -- |
