Engine Overheating

Step	Action	Yes	No
DEFINITION: The malfunction indicator lamp (MIL) comes on and stays on, the engine temperature lamp comes on and stays on, or temperature gauge shows hot, or coolant overflows from the surge tank onto the ground while the engine is running.
1	Check for stored diagnostic trouble codes (DTCs). Diagnostic System Check - Vehicle Are there any stored diagnostic trouble codes (DTCs)?	Go to Step 2	Go to Step 3
2	Check Symptoms - Engine Coolant Symptoms - Engine Cooling Does the engine still overheat?	Go to Step 3	System OK
3	Check for a loss of coolant. Loss of Coolant Is there a loss of coolant?	Go to Step 4	Go to Step 5
4	Fill the system to the specified level. Cooling System Draining and Filling (GE-47716) , or Cooling System Draining and Filling (Static) Does the engine still overheat?	Go to Step 5	System OK
5	Check for kinked or pinched surge tank hoses, especially at the radiator. Are any surge tank hoses kinked or pinched?	Go to Step 6	Go to Step 7
6	Relieve any kinks by rerouting the hoses. Replace the hoses, if necessary. Does the engine still overheat?	Go to Step 7	System OK
7	Check for loose, missing, or damaged radiator air seals or deflectors. Are there any loose, missing, or damaged radiator air seals or deflectors?	Go to Step 8	Go to Step 9
8	Repair or replace any loose, missing, or damaged radiator air seals or deflectors. Does the engine still overheat?	Go to Step 9	System OK
9	Check the coolant concentration. Does the coolant concentration test correctly?	Go to Step 11	Go to Step 10
10	Replace the coolant, if necessary. Cooling System Draining and Filling (GE-47716) , or Cooling System Draining and Filling (Static) Does the engine still overheat?	Go to Step 11	System OK
11	Check the system for loss of coolant. Loss of Coolant Is there a loss of coolant?	Go to Step 12	Go to Step 13
12	Repair any leaks, as necessary. Does the engine still overheat?	Go to Step 13	System OK
13	Check for a faulty engine coolant temperature sensor. Is the engine coolant temperature sensor faulty?	Go to Step 14	Go to Step 15
14	Replace the engine coolant temperature sensor. Engine Coolant Temperature Sensor Replacement - Engine Coolant Flow Control Valve (L3T) Does the engine still overheat?	Go to Step 15	System OK
15	Check the radiator for any air flow obstructions or bent fins. Is there any airflow obstruction or bent fins?	Go to Step 16	Go to Step 17
16	Remove or relocate add-on parts that block air flow to the radiator. Clean any debris from the radiator core. Does the engine still overheat?	Go to Step 17	System OK
17	Check for any blocked cooling system passages. Are there any blocked cooling system passages?	Go to Step 18	Go to Step 19
18	Remove any obstruction. Flush the cooling system, as required. Coolant System Flushing Refill the coolant. Cooling System Draining and Filling (GE-47716) , or Cooling System Draining and Filling (Static) Does the engine still overheat?	Go to Step 19	System OK
19	Check for an inoperative cooling fan. Is the cooling fan inoperative?	Go to Step 20	-
20	Replace the cooling fan. Engine Coolant Fan Replacement Does the engine still overheat?	-	System OK