Description
This is the power source for the tire pressure warning ecu.
Wiring diagram

Inspection procedure
Notice:
It is necessary to register an id code after replacing the tire pressure monitor valve and/or the tire pressure warning ecu (see page tw-9).
Standard resistance:
below 1 


Standard resistance

Standard voltage 
Standard resistance 
Proceed to next circuit inspection shown in problem symptoms table
Tire pressure warning light circuit
Tire pressure warning receiver (w/ antenna)Ventilation valve
Components
Removal
Remove no. 1 Engine cover (see page em-22)
Remove ventilation valve sub-assembly
Disconnect the ventilation hose from the ventilation
valve.
Using a 22 mm deep socket wrench, remove the
ventilation valve.
Inspection
Inspect ventilation val ...
Removal
Disconnect cable from negative battery
terminal
Caution:
Wait at least 90 seconds after disconnecting the
cable from the negative (-) battery terminal to
prevent airbag and seat belt pretensioner activation.
Remove air cleaner cap (see page es-411)
Remove air cleaner case
...
Mass or volume air flow circuit
Description
The mass air flow (maf) meter is a sensor that measures the amount of air
flowing through the throttle
valve.
The ecm uses this information to determine the fuel injection time and to
provide the appropriate air-fuel
ratio.
Inside the maf meter, there is a heated platinu ...