Pinpoint Test A: Loss of Coolant

Powertrain Secondary Cooling System

Pinpoint Tests

Pinpoint Test A: Loss of Coolant

Normal Operation

The secondary cooling system is a closed system that provides for coolant expansion and contraction and also changes in pressure as coolant warms and cools with engine operation. Various gaskets, seals, hoses and clamps are used to contain coolant within the cooling system and keep other fluids and contaminants from entering the cooling system.

Coolant loss can be attributed to either external or internal leaks anywhere within the cooling system.

This pinpoint test is intended to diagnose the following:
- Coolant hoses or tubes
- Hose clamps
- Quick connect couplings
- Thermostat O-ring seal or gasket
- Coolant pump O-ring seal or gasket
- Radiator
- Pressure relief cap
- Coolant pump leaking from weep hole
- Degas bottle
- Transmission fluid cooler
- EGR cooler
- CAC
- Fuel cooler
- Engine Coolant Temperature (ECT) sensor - secondary cooling system ECT2

PINPOINT TEST A: LOSS OF COOLANT

WARNING: Always allow the engine to cool before opening the cooling system. Do not unscrew the coolant pressure relief cap when the engine is operating or the cooling system is hot. The cooling system is under pressure; steam and hot liquid can come out forcefully when the cap is loosened slightly. Failure to follow these instructions may result in serious personal injury.

-------------------------------------------------
A1 CARRY OUT INSPECTION AND VERIFICATION

- Carry out the Inspection and Verification procedure. Inspection and Verification
- Were any concerns found?

Yes
REPAIR as needed. TEST the system for normal operation.

No
GO to A2.

-------------------------------------------------
A2 CHECK THE COOLANT LEVEL

NOTE: Allow the engine to cool before checking the coolant level.

- Ignition OFF.
- Visually inspect the coolant level at the degas bottle.
- Is the coolant level within specifications?

Yes
GO to A3.

No
ADJUST the coolant level as necessary. GO to A3.

-------------------------------------------------
A3 PRESSURE TEST THE POWERTRAIN SECONDARY COOLING SYSTEM

- Pressure test the cooling system. Refer to Component Tests, Cooling System Pressure Test. Component Tests
- Does the cooling system leak?

Yes
REPAIR or INSTALL new components. TEST the system for normal operation.

No
GO to A4.

-------------------------------------------------
A4 CHECK THE COOLANT FOR TRANSMISSION FLUID

- Inspect the coolant in the degas bottle for signs of transmission fluid.
- Is transmission fluid evident in the coolant?

Yes
INSTALL a new transmission fluid cooler. REFER to Transaxle/Transmission Cooling Transmission Fluid Cooler. REPAIR the transmission as necessary. TEST the system for normal operation.

No
GO to A5.

-------------------------------------------------
A5 CHECK THE TRANSMISSION FLUID FOR COOLANT

- Remove the transmission fluid level indicator.
- Is coolant evident in the transmission fluid?

Yes
INSTALL a new transmission fluid cooler. REPAIR the transmission as necessary. TEST the system for normal operation.

No
GO to A6.

-------------------------------------------------
A6 CHECK THE COOLANT FOR FUEL

- Inspect the coolant in the degas bottle for signs of fuel.
- Is fuel evident In the coolant?

Yes
INSTALL a new fuel cooler. REFER to Fuel Charging and Controls - Fuel Cooling System Service and Repair. TEST the system for normal operation.

No
GO to A7.

-------------------------------------------------
A7 CHECK FOR COOLANT IN THE FUEL

- Drain the fuel from the fuel conditioning module and check for coolant in the fuel.
- Is coolant evident in the fuel?

Yes
INSTALL a new fuel cooler. REFER to Fuel Charging and Controls - Fuel Cooling System Service and Repair. TEST the system for normal operation.

No
GO to A8.

-------------------------------------------------
A8 CHECK THE CAC FOR AN INTERNAL LEAK

- CARRY OUT the CAC leak test. REFER to Intake Air Distribution and Filtering Testing and Inspection.
- Does the CAC leak?

Yes
INSTALL a new CAC. REFER to Intake Air Distribution and Filtering Removal and Replacement. TEST the system for normal operation.

No
GO to A9.

-------------------------------------------------
A9 CHECK THE EGR COOLER FOR AN INTERNAL LEAK

- CARRY OUT the EGR cooler leak test. REFER to Engine Emission Control Procedures.
- Does the EGR cooler leak?

Yes
REPAIR the EGR cooler as necessary. TEST the system for normal operation.

No
The cooling system is operational.

-------------------------------------------------