B1287

DTC B1287

DTC Descriptors

DTC B1287 01
- Amplifier Control Signal Circuit Short to Battery

DTC B1287 02
- Amplifier Control Signal Circuit Short to Ground

DTC B1287 04
- Amplifier Control Signal Circuit Open

Diagnostic Fault Information

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview






Circuit/System Description

The radio provides a remote amp mute output circuit to control overall muting of remote non-GMLAN amplifiers with rear seat audio (RSA) applications. The amplifier receives PWM signals on the circuit at varying duty cycle percentages for controlling the muted and unmuted functions of the amplifier. The RSA enable circuit in the radio enables the rear seat channel muting of the amplifier. A diagnostic sense circuit internal to the radio monitors the remote amp mute circuit for faults and sets the appropriate DTC when detected.

Conditions for Running the DTC

The following are conditions that must be present in order for the radio to enable the diagnostics.

* The radio is in ACCESSORY, RUN, or RAP power mode.
* The system voltage is at least 9 volts and no more than 16 volts.

Conditions for Setting the DTC

Circuit failure 400 ms after radio activates Remote Enable.

Action Taken When the DTC Sets

Radio sets the DTC and continues to output correct state.

Conditions for Clearing the DTC

* The condition must be corrected.
* A history DTC clears after 100 malfunction free ignition cycles.
* The radio receives the clear code command from the scan tool.

Circuit/System Verification

Verify the audio system performance by adjusting the fade and balance of the speaker outputs.

Circuit/System Testing

Ignition OFF, test the remote radio control signal circuit for an open, a short to voltage, or a short to ground.

If the circuit tests normal, replace the radio.


Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

Programming and Relearning for radio setup, and programming. Programming and Relearning