navi install

[rlh0153]

I have installed a Denso nav unit from a 2008 GXP into my 2005 GT. No Monsoon, but do have OnStar. Factory unit is the CD/AM/FM radio. Problem - the volume will not adjust to get louder. It is very low level and will not increase. Any info to aid in resolving this issue is appreciated.

SW controls work, but no door chime or key in ignition warning. I am told this unit has no amp and that Monsoon wiring cluster (premium sound) may be required.

[industrialfish]

That sounds about right. Pretty sure you couldn't get the nav system without getting the premium sound upgrade package first.

[rlh0153]

Thanks. This has been one big expensive lesson to learn, and still not done.

[industrialfish]

You should give up on it and trade it to me lol.

[rlh0153]

No lol. Trade for what?

[rodman]

I have installed a Denso nav unit from a 2008 GXP into my 2005 GT. No Monsoon, but do have OnStar. Factory unit is the CD/AM/FM radio. Problem - the volume will not adjust to get louder. It is very low level and will not increase. Any info to aid in resolving this issue is appreciated.

SW controls work, but no door chime or key in ignition warning. I am told this unit has no amp and that Monsoon wiring cluster (premium sound) may be required.

Any update ?