_GM (8S8) - Backup Reversing Alarm
Backup Alarm
For installation of backup alarms on units with out option code 8S3 factory backup alarm a connection can be made at the rear lighting connector X-405-H Light Green 1624 wire. The backup lamps illuminating the perimeter lighting and key fob acknowledgement modes are correct operation of the backup alarm:
- Return the unit to a GM dealer to have the BCM software for option 8S3 loaded. This is a fee for service activity.
- Install an ignition controlled relay to connect the alarm to the 1624 wire such that the relay is closed [alarm connected] with key on.
See simplified schematic:
