Circuit/System Description
WARNING: This page is about a different car, the 2008 Saturn Outlook, 2008 GMC Acadia, and 2008 Buick Enclave. However, it is still accessible from the selected car via links, so may be relevant.
The radio provides a remote amp enable output circuit to control overall muting of remote amplifiers. The amplifier receives pulse width modulated (PWM) signals on the circuit at varying duty cycle percentages for controlling the muted and unmuted functions of the amplifier. A diagnostic sense circuits internal to the radio monitor the remote amp enable circuit and amp control circuit for a fault and sets the appropriate DTC when detected.