Vehicle Speed Signal Circuit between Stereo Component Amplifier and Combination Meter [08/2013 - ]: Description

The stereo component amplifier assembly receives a vehicle speed signal from the combination meter assembly to control the Automatic Sound Levelizer (ASL) function.

HINT: 

• A voltage of 12 V or 5 V is output from each ECU and then input to the combination meter assembly. The signal is changed to a pulse signal at the transistor in the combination meter assembly. Each ECU controls the respective systems 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.