Speed Signal Circuit: Description

The headlight leveling ECU assembly receives the vehicle speed signal from the combination meter sub-assembly.

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 the 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, all systems in the diagram below will not operate normally.