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Loss of Coolant (LM2)

Step Action Yes No
DEFINITION: The cooling system is losing coolant either internally or externally.
1 Were you sent here from Symptoms or another diagnostic table? Go to Step 2  Go to Symptoms - Engine Cooling 
2 Repair any present DTCs. Diagnostic System Check - Vehicle
Is the action complete?		 Go to Step 3  -
3 Inspect the coolant level.
Is the coolant at the proper level?		 Go to Step 5  Go to Step 4 
4 Fill the cooling system to the proper level.
Is the action complete?		 Go to Step 5  -
5 If the engine is suspected to have a coolant leak into a cylinder, the coolant can hydraulically lock the engine.
Does the engine crankshaft rotate?		 Go to Step 6  Go to Step 27 
6 Engine overheating can cause a loss of coolant.
Is the engine overheating?		 Go to Step 28  Go to Step 7 
7 Extended operation with a low coolant level can cause engine internal component failure.
Is the engine knocking?		 Go to Step 30  Go to Step 8 
8
  1. Idle the engine at normal operating temperature.
  2. Inspect for heavy white smoke coming out of the exhaust pipe.
Is a heavy white smoke present from the exhaust pipe?		 Go to Step 9  Go to Step 10 
9
  • Coolant in the exhaust system creates a distinctive, burning coolant odor in the exhaust.
  • Condensation in the exhaust system can cause an odorless white smoke during engine warm up.
Does the white smoke have a burning coolant type odor?		 Go to Step 29  Go to Step 10 
10
WARNING:

Refer to Moving Parts and Hot Surfaces Warning .

With the engine idling, inspect the coolant recovery system.Does the coolant recovery system discharge coolant while the engine is idling?		 Go to Step 14  Go to Step 11 
11 Visually inspect the coolant hoses, pipes and hose clamps at the following locations:
  • Charge Air Cooler(s)
  • Engine Radiator(s)
  • Heater Core
  • Radiator Surge Tank
  • Throttle Body
  • Water Pump

Are any of the coolant hoses, clamps or pipes leaking?		 Go to Step 20  Go to Step 12 
12 Visually inspect the following components:
  • Charge Air Cooler(s)
  • Core Plugs
  • Cylinder Head Gaskets
  • Engine Block
  • Engine Oil Cooler Assembly
  • Engine Radiator(s)
  • Intake manifold
  • Radiator Surge Tank Cap
  • Thermostat Housing
  • Water Pump

Are any of the listed components leaking?		 Go to Step 20  Go to Step 13 
13
  1. Pressure test the cooling system. Cooling System Leak Testing 
  2. With the cooling system pressurized, visually inspect the components listed in steps 11 and 12.
Are any leaks present?		 Go to Step 20  Go to Step 14 
14 Pressure test the radiator surge tank cap. Radiator Surge Tank Cap Testing 
Does the radiator surge tank cap hold pressure?		 Go to Step 15  Go to Step 21 
15 Inspect for the following conditions:
  • A coolant smell inside of the vehicle
  • Coolant in the heater and air conditioning evaporator and blower module removal drain tube
  • Coolant on the vehicle floor covering near the heater and air conditioning evaporator and blower module

Is coolant present?		 Go to Step 22  Go to Step 16 
16
  1. Add 30 ml (1 oz) of coolant system tracer dye to the cooling system for each 15 L (4 gal) of coolant.
  2. Start the vehicle and allow the engine to reach normal operating temperature.
  3. Shut the engine off.
  4. Use the GE-42220  Universal 12V Leak Detection Lamp to visually inspect the components listed in steps 11 and 12.
Are any leaks present?		 Go to Step 20  Go to Step 17 
17 Use the GE 42220  Universal 12V Leak Detection Lamp to inspect for the following conditions:
  • Coolant system tracer dye in the heater and air conditioning evaporator and blower module drain tube
  • Coolant system tracer dye on the vehicle floor covering near the heater and air conditioning evaporator and blower module

Is coolant dye present?		 Go to Step 22  Go to Step 18 
18 Inspect the underside of the engine oil fill cap for a gray/white milky substance.
Is a milky substance under the oil fill cap?		 Go to Step 19  Go to Step 20 
19 Inspect the engine oil fluid level indicator for a gray/white milky substance.
Is a milky substance on the engine oil fluid level indicator?		 Go to Step 29  Go to Step 23 
20 Repair or replace the leaking component.
Is the repair complete?		 Go to Step 31  -
21 Replace the radiator surge tank cap.
Is the repair complete?		 Go to Step 31  -
22 Replace the heater core.
Is the repair complete?		 Go to Step 31  -
23 Visually inspect the coolant hoses, pipes and hose clamps at the following locations:
  • Charge Air Cooler
  • Charge Air Cooler Coolant Pump
  • Charge Air Cooling System Hoses
  • Compressor Air Intake Supercharger
  • Engine Radiator Intercooler Heat Exchanger

Are any of the hoses, clamps or pipes leaking?		 Go to Step 20  Go to Step 24 
24 Visually inspect the following components:
  • Charge Air Cooler
  • Charge Air Cooler Coolant Pump
  • Compressor Air Intake Supercharger
  • Engine Radiator Intercooler Heat Exchanger

Are any of the listed components leaking?		 Go to Step 20  Go to Step 25 
25
  1. Pressure test the charge air cooling system. Charge Air Cooling System Leak Testing (LM2) 
  2. With the charge air cooling system pressurized, visually inspect the components listed in steps 23 and 24.
Are any leaks present?		 Go to Step 20  Go to Step 26 
26
  1. Add 30 ml (1 oz) coolant system tracer dye to the cooling system for each 15 L (4 gal) of coolant.
  2. Activate the pump using the MDI to cycle the dye around the charge air cooling system.
  3. Shut the engine off.
  4. Use the GE-42220  Universal 12V Leak Detection Lamp to visually inspect the components listed in steps 23 and 24.
Are any leaks present?		 Go to Step 20  Go to Step 31 
27 Repair the engine no crank condition. Engine Will Not Crank - Crankshaft Will Not Rotate
Is the repair complete?		 Go to Step 31  -
28 Repair the engine overheating condition. Engine Overheating (LM2) 
Is the repair complete?		 Go to Step 31  -
29 Repair the engine internal coolant leak.
Is the repair complete?		 Go to Step 31  -
30 Repair the engine knock. Lower Engine Noise, Regardless of Engine Speed
Is the repair complete?		 Go to Step 31  -
31 Operate the system in order to verify the repair.
Did you find and correct the condition?		 System OK Go to Step 2 
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