Cooling System: Description and Operation

DESCRIPTION
This system utilizes a reverse flow cooling system with a cold side thermostat. In reverse flow cooling, the coolant flows from the radiator, to the water thermostat and to the cylinder heads.

COMPONENTS
The cooling system includes the following components:
- Radiator.
- Water pump.
- Water thermostat.
- Engine cooling fan motor and fan blade which are activated by the Powertrain Control Module (PCM).
- radiator coolant recovery reservoir located on the RH fender apron. The reservoir aids in maintaining the correct volume of engine coolant and contributes to the de-aeration of the cooling system.

WATER PUMP
The water pump is a self-contained, remote-mount design and mounted on the LH cylinder head. It is driven from the rear of the LH intake camshaft by a separate drive belt.

WATER THERMOSTAT
The water thermostat is located in the water pump housing inlet which is attached to the LH cylinder head.

COOLING FAN, ELECTRIC

WARNING: THE ENGINE ELECTRIC COOLING FAN MOTOR MAY COME ON AT ANY TIME WITHOUT WARNING WITH THE IGNITION SWITCH IN THE RUN POSITION, EVEN IF THE ENGINE IS NOT RUNNING.

The cooling fan motors are wired to operate only when ignition switch is in the RUN position, thereby preventing radiator electric motor operation after the ignition switch is turned to the OFF position. The fan control system consists of:
- Powertrain Control Module (PCM).
- Related wiring.
- Two, two-speed cooling fan motors attached to a fan shroud located behind the radiator.
- A/C cycling switch.
- A/C clutch coil circuit.
- Cooling fan relays (Constant Control Relay Module).