Circuit/System Description
Each of the audio output channel circuits (+) and (-), at the radio and audio amplifier have a DC bias voltage that is one half of the battery voltage.
When using a DMM, each of the audio output channel circuits will measure approximately 6.5V DC. The audio being played on the system is
produced by a varying AC voltage that is centered around the DC bias voltage on the same circuit. The AC voltage is what causes the speaker cone
to move and produce sound. This voltage will vary depending on what type of audio is being listened to, talk or music, and type of music, as well as
the volume setting of the system. Low volume and talk settings will measure around 1V AC and less, where constant music may measure 3V AC and
slightly higher.
Conditions for Running the DTC
The radio is ON.
Conditions for Setting the DTC
Set by Radio
The radio sets a current status for this DTC when a short to ground, short to voltage or an open is detected on any of the speaker channel outputs
from the radio.
Set by Bose Amplifier
The DTC will not set during normal amplifier operation. The vehicle must have the ignition OFF for several hours and the fault must be present
during amplifier power-up.
DTC B1025 01, B1035 01, B1045 01, B1055 01, B1065 01, B1075 01, B1085 01, B1095 01
A short to voltage is detected on the specified (+) or (-) signal circuit
DTC B1025 02, B1035 02, B1045 02, B1055 02, B1065 02, B1075 02, B1085 02, B1095 02
A short to ground is detected on the specified (+) or (-) signal circuit
DTC B1025 04, B1035 04, B1045 04, B1055 04, B1065 04, B1075 04, B1085 04, B1095 04
An open is detected on the specified (+) or (-) signal circuit
Action Taken When the DTC Sets
No sound is present from one or more of the speakers.
Conditions for Clearing the DTC
Set by Radio
The fault condition becomes history if not present for 0.25 seconds.
Set by Bose Amplifier
The fault condition becomes history after the vehicle ignition has been OFF for several hours and then the ignition turns ON.