Hi...I am new to the site and have been searching for a thread that might address my issue but was unable to find one...so here goes:

I have an AVIC-Z1 installed in a 2007 Trailblazer SS. After I left the installer, everything worked great on the way home. The next day, the unit starting changing stations in XM on its own. It woud change to a different category, go forward stations/go backward stations, cycle through all of this quickly.

I changed the source to FM and it did the same thing.

I tried it with the DVD...it did the same thing again (kept skipping to different chapters).

I have the steering wheel controls installed...but what it weird is the XM jumping to different categories (a function not enabled with my steering wheel controls).

It doesn't start immediately upon starting the car and occassionally doesn't happen at all, but once it starts...there is no stopping it.

Has anyone seen similar problems to this before?

check steering wheel interface, likely that is what is causing the problem even if its a button not normally there

Yes have the steering wheel control reprogrammed. That is in my experiences what causes that problem every time.

Ok... I have two trailblazers. Both have had this problem. After my dealer spent lots of time reprogramming and such, the real fix was this:

The factory steering wheel control wire needs to be "cut" and "spliced" into the steering wheel control mudule.

If you just "tap" into the wire, the factory system will send signals that will cause the radio to change stations radomly.

Once my dealer did this I have had no problems!

This was the solution that was worked out with PAC technicle support.

By the way, I have an 07 SS too! Love my truck!

Good Luck!

correct me if i'm wrong, but don't the instructions say to cut the wire for the steering control interface? I could be wrong been a while since I did one in a gm.

and of course you connect the single wire of the car to the swi then program it. how else where they installing this thing?

Thanks for the help. After I had the steering wheel controls rewired, the problem started to happend again...turns out this time it was the handheld remote. Once I removed that as well...no problems.

and of course you connect the single wire of the car to the swi then program it. how else where they installing this thing?

I think they spliced and twisted the PAC wire into my factory wire for the steering wheel control.

I don’t know if the directions say to "cut" the factory wire but even it does say "cut" without a side note that it must really be cut or problems will occur, many probably strip back the insulation and twist the wire on.

Because this happened in two different trailblazers I own I thought it was for sure a valid fix.

yeah good catch, pac should make this info more available probably. btw, an outside company most likely did the work for the dealership you took your vehicle to. just an fwi

Wow. I have exactly the same problem (same vehicle, deck and everything). Would you mind putting up a bit of a diagram on this? To splice a wire I thought you would have two wires to connect. Are you saying that the fix was just to bare the wire and twist the 2 together? This just dos not seem to be much of a differnece compared to tapping the wire.

Thanks for your help.

Look at the plug at the SWIPS module. The brown loop on the plug needs to be cut. This happens with many GM SUV's.

Wow. I have exactly the same problem (same vehicle, deck and everything). Would you mind putting up a bit of a diagram on this? To splice a wire I thought you would have two wires to connect. Are you saying that the fix was just to bare the wire and twist the 2 together? This just dos not seem to be much of a differnece compared to tapping the wire.

 

Thanks for your help.

I'm not sure if you are asking me, referring to my post?

But just in case, when I say cut, I mean sever the factory wire in two, then attach one of the ends to the PAC module.

When I say strip back the insulation and twist the wire onto it, then there is no cutting involved. You strip back some of the insulation on the factory wire to expose the copper and just twist the PAC wire around it.

I had mine installed and this is the information the installer passed onto me.

As long as you cut the brown loop on the SWIPS module, you should be able to just tap into the steering wheel control wire, which is light green at pin 12 of the harness coming from the column. Make sure the SWIPS is programmed for version 1. You can verify this by looking at the SWIPS when you turn on the ignition, the red LED should blink once.

Wow. I have exactly the same problem (same vehicle, deck and everything). Would you mind putting up a bit of a diagram on this? To splice a wire I thought you would have two wires to connect. Are you saying that the fix was just to bare the wire and twist the 2 together? This just dos not seem to be much of a differnece compared to tapping the wire.

 

Thanks for your help.

 

I'm not sure if you are asking me, referring to my post?

 

But just in case, when I say cut, I mean sever the factory wire in two, then attach one of the ends to the PAC module.

 

When I say strip back the insulation and twist the wire onto it, then there is no cutting involved. You strip back some of the insulation on the factory wire to expose the copper and just twist the PAC wire around it.

 

I had mine installed and this is the information the installer passed onto me.

ok. When the wire is cut, can you clarify which lines on the PAC module are connected to the factory wire. We've tried several things but to no avail so far.

Thanks

The side that goes back towards the steering wheel.

This is a common problem with Trailblazers and Envoy's. The techs at PAC were aware of this problem, but it took three calls before they would own up to it. I've tried just splicing( w/ brown loop cut) and cutting the steering wheel wire loose from the BCM and connecting it straight to the PAC piece( w/ brown loop un-cut). The later worked best for me, but it still has the same problem, just not as offen. When the wire is cut you will loose the control of on-star from the steering wheel. On the plus side, you can use that button to control one more feature on the radio.

I haven't had any problems with the SWIX as long as you cut the brown loop on GM SUV's in a while, my SWIX's must be newer. Although, putting one in a 2000-up 3-series BMW does some funky stuff for the first 10 seconds or so after turning on the key, because the same wire sends an "all is well" signal from the steering wheel to the computer. I've also found that if you disconnect power from the SWIPS while the ground and signal wires are still connected and the radio is still powered up, (back on subject) the SWIPS will start sending out signals and making the radio do some strange things, like change source, usually. Check that your accessory lead to the SWIPS is good and solid and cycles the same as the radio accessory lead and does not shut off while the radio is powered up.