How To: Sirius Sir-gm1 Install In Non-xm Truck

[sam988]

After reading a ton of posts on a variety of forums I noticed that there were no good tutorials on how to install a SIR-GM1 receiver in a non-XM truck (Silverado/Sierra/Tahoe/Yukon/Avalanche/etc.). So I figured I'd write one.

 

Two of the biggest complaints and grievances that everyone talks about with this install are the lack of space to mount the receiver under the dash and that the supplied T-harness is too short. The best place to mount the receiver is on its side on top of one of the main dash support beams and against one of the heater ducts (see picture below). It fits nice and snug and the T-harnes is the perfect length.

 

To get the module into this area, remove the radio and HVAC controls (just let them hang), remove the plastic cubby hole beneath the vent, drop the glovebox down, and pop out the left passenger vent. This gives you plenty of room to finesse the receiver into place.

 

If you bend the middle mounting tab on the left side of the module (now the top) it will fit perfectly between the right drivers vent and the support beam (behind the wiring harness that is strapped to the beam). This puts the back of the receiver against a large flat area on the main duct. Mounting it this way allows for plenty of room to access the module harness plug on the left and the antenna on the right. Be sure to test fit everything first as it's a lot easier to make adjustments at this point.

 

 

 

I prefit all the wiring before cutting anything or making any connections. The T-harness fit perfectly with the radio connector coming in through the top left corner of the radio bay along side the main radio harness. The SIR-GM1 connector went in behind the HVAC bay to the receiver behind the cubby hole.

 

 

For the power and the ground I ran the yellow and black wires down to the fuse panel. If you drop the plastic cover from below the steering column you have tons of room to run the wires and can easily access bolts to ground to. I grounded to a bolt on the steering column bulkhead where my remote start was grounded. As for an "always hot" power source I bought an "Add-A-Circuit" from Canadian Tire. It goes in place of an existing fuse and adds a fused hot-wire without affecting the original component. Whoever thought of that setup is a genius!

 

 

After all the wiring was done, taped, and zip-tied, I mounted the reciever to the heater duct with a couple of pieces of double-sided foam body moulding tape. The reciever doesn't move at all and so far there haven't been any heat related issues. I also mounted the small plastic box on the power harness with the fuse and filter in it onto a brace beneath the steering column with the two-sided tape.

 

 

For the time being, I just mounted the antenna on the corner of the dash on the drivers side. Depending on its performance I might run it out of my third brake light onto the roof in the spring.

 

Overall, I'm really happy with the install and could probably do it again in about 45 min to an hour. The unit works great, I only wish that the SIR-GM1 supported text scrolling. Oh well, beggars can't be choosers, and in my mind it still beats a plug and play unit.