Cadillac CTS/SRX Radio Replacement PDF Installation Instructions

The GM20SR is a plug and play interface that allows replacement of a General Motors Class II factory stereo in Cadillac CTS and SRX vehicles. It will maintain operation of the OnStar and factory amplified systems. The system to play through the two front factory GM20SR has on board switching to allow audio from the OnStar speakers when OnStar is active. It also retains warning chimes for Onstar operation. For additional vehicle integration, use Scosche’s line of SWC-1 steering wheel controls (SWC) interfaces to retain SWC’s with the aftermarket radio. Also retains Vehicle Parking Assist chimes.

Class II circuitry will not disable vehicle data bus even if interface loses power. OnStar active LED and Ignition on LED. Provides +12v switched accessory output. No more searching for switched +12v in fuse box or kick panel. Mute output to either mute the aftermarket radio or to turn it off when OnStar is active. OnStar Volume control via factory steering wheel audio controls or click wheel .New radio will operate with the vehicle RAP (Retained Accessory Power) system, stays on after the key is turned off and for 10 minutes or until a door is opened.

NOTE: New vehicles are constantly being researched. If your vehicle is not listed above, check our web site for any new updates or instructions. Due to the design of the Standard Amplified system, there is currently no way of fading from front to rear with an aftermarket radio. Step 1. rewire the GM20SR 18-pin wire harness to the aftermarket stereo wire harness. If the aftermarket stereo has a mute wire, cut the brown wire as close as possible to pin #16 of the GM20SR 18-pin harness and connect this mute output wire to the stereo’s mute wire. The amp remote wire (Blu/Wht) must be connected to the stereo’s remote wire. Connect the 16-pin wire harness to the GM20SR main interface. Step 2. Connect the black 8-pin, brown 8-pin, and the red 20-pin harness to the factory radio harnesses. Connect the 16-pin wire harness into the GM20SR.

Download Cadillac CTS/SRX Radio Replacement PDF Installation Instructions