Purpose, Function
The cooling system cap maintains appropriate pressure in the engine coolant passage. In addition, cooling efficiency has been improved by increasing the engine coolant boiling point.
Construction
The cooling system cap is installed to the upper part of the radiator.

Operation
When engine coolant temperature is high
1. When the engine coolant temperature is high, the pressure in the engine coolant passage increases and the pressure valve is pressed and opened.
2. Engine coolant flows into the coolant reserve tank when the pressure valve is open.

When engine coolant temperature is low
1. When the engine coolant temperature is low, the pressure in the engine coolant passage decreases and the vacuum valve is opened.
2. Engine coolant in the coolant reserve tank flows into the engine coolant passage when the vacuum valve is open.

Cooling System Cap Inspection
Cooling System Service WarningsHydraulic Lash Adjuster (Hla) Removal/Installation
WARNING:
A hot engine can cause severe burns. Turn off the engine and wait until it
is cool before servicing.
CAUTION:
If the camshaft is rotated with the timing chain removed and the piston at
the top dead center position, the valve may contact the piston and the engine ...
Coolant Reserve Tank Removal/Installation
1. Remove in the order indicated in the table.
2. Install in the reverse order of removal.
1
Wiring harness
2
Hose
3
Coolant reserve tank
(See Coolant Reserve Tank Removal Note.)
Coolant Reserve Ta ...
Hood Latch Switch
Purpose
Detects the open/closed condition of the hood.
Function
The hood latch switch is utilized in the theft-deterrent system control.
For the theft-deterrent system, refer to (see THEFT-DETERRENT SYSTEM.).
Construction
Built into the hood latch ...