Hint:

Standard voltage: 11 to 14 v
If the voltage is below 11 v, recharge or replace the battery before proceeding.
Result 

Result 

Result 

End
System description
How to proceed with troubleshooting (2006/01- )Toyota Safety Sense 2.5
The Toyota Safety Sense
2.5 consists of the following
drive assist systems and
contributes to a safe and
comfortable driving experience:
Driving assist system
PCS (Pre-Collision System)
LTA (Lane Tracing Assist)
AHB (Automatic High
Beam)
RSA (Road Sign Assist) (if
equipped)
Dynamic radar cru ...
Disassembly
Remove no. 1 Side defroster nozzle duct
Remove the 3 screws and duct.
Remove no. 2 Side defroster nozzle duct
Remove the 3 screws and duct.
Remove no. 1 Heater to register duct
Remove the screw and duct.
Remove no. 2 Heater to register duct
...
Ecm power source circuit
Description
When the ignition switch is turned on, the battery voltage is applied to the
igsw of the ecm. The output
signal from the mrel terminal of the ecm causes a current to flow to the coil,
closing the contacts of the
integration relay (efi main relay) and supplying power to either term ...