Power Source Circuit: Description
WARNING: This page is about a different car, the 2007 Lexus ES 350. However, it is still accessible from the selected car via links, so may be relevant.
This circuit is the power source for the clock assembly. This circuit provides two types of power sources; one is a constant power source mainly used as a backup power source, and the other is a power source mainly used for signal transmission. The constant power source is mainly used as a backup power source of the clock assembly, however, it is also used for communication.
HINT:
If the clock assembly displays "1:00" when the engine switch is turned off, then on (IG) again, the +B (*1)/B (*2) terminal has a malfunction.
The maximum clock assembly margin of error is -4 to 4 seconds per day when the temperature is between -20°C (-4°F) and 60°C (140°F).