Vehicle Speed Signal Circuit between Navigation Receiver Assembly and Combination Meter: Description

WARNING: This page is about a different car, the 2008 Toyota Tundra. However, it is still accessible from the selected car via links, so may be relevant.

This circuit sends a speed signal from the combination meter to the navigation receiver.

HINT:

A voltage of 12 V or 5 V is output from each ECU and then input to the combination meter. The signal is changed to a pulse signal at the transistor in the combination meter. Each ECU controls its respective system based on the pulse signal.
If a short occurs in any of the ECUs or in the wire harness connected to an ECU, both systems in the diagram below will not operate normally.