Interface confusion

[IndianaEXT]

Forgive me for starting another thread about wiring harnesses but I'm seriously scratching my head here. I have scored these threads here and cant nail down a strong answer between all the replies and posts.

Feel like I'm in the same boat as this guy:

https://gmtnation.com/forums/threads/2005-tb-bose-harness-confusion.7575/


I have a 2005 LT EXT. 6 Disc CD changer, xm, am/fm, Bose, On star, and also had the overhead DVD with digital controls and headphones in the middle seating.

I have asked crutchfield and get mixed answers. Get the same from others.

I am not so concerned with keeping steering wheel controls as the radio is right there. I am not concerned at all about On star as it is never and will never be used. The rear dvd is inoperable at the moment as it does not read discs for some reason.

I would like to say that I will be upgrading door speakers to aftermarket amps in the future but for now I have an amp for the subs only.

The million dollar question is, do I need to get a more expensive Pac controller (and which one) or would the gmos-04 suffice for my needs?

This is no show car and I will be the one who ultimately rolls this baby to her grave so again I'm not concerned about losing functionality of things in the truck that I don't use or will never use.

Asb always any guidance would be greatly appreciated.

 

[Mooseman]

Are you using the Bose amp? If so, you need one compatible with that. On the Bose system, you can't just replace speakers as they are components.

The GMOS-04 works with the Bose but is plagued with failures. The PAC units are much more reliable.

 

[IndianaEXT]

Yes, as of now I am using the Bose amp.

My wish list would be to bypass that altogether and just use aftermarket amps and speakers.

But for now I have a new head unit to install and subs and amp from previous ride.

 

[Mooseman]

If retaining Bose, you need that interface. After you eventually dump the Bose, you can keep using it but just unplug the RCA's to the interface so you can use them with your new setup. That way, you also retain RAP and chimes will work through the PAC's internal speaker.

 

[IndianaEXT]

Sounds like PAC it is! Would this particular one that Crutchfield suggested suffice:

https://www.crutchfield.com/p_541RP5GM11/PAC-RP5-GM11-Wiring-Interface.html

 

[Matt]

Personally, I'd go with the GMOS-04, but if you get the PAC unit, buy it from Amazon and save yourself about $20.

 

[Mooseman]

Get the RP4-GM11. The RP5 retains OnStar. Cheaper. And like @Sparky said, go Amazon.

 

[IndianaEXT]

Thanks fellas....just the kind of info I was hoping to get!

 

[Sparky]

@Mooseman you mean as @Matt said

 

[Matt]

Yeah, I know we're both from Ohio, but I'm the old fat one, not the young , slim, good looking one!

 

[IndianaEXT]

So I went with the rp4-gm11 interface and want to ask before I solder and make a fool of myself.

Coming off the Rp4 I have 4 wires left and not sure what to do with them:

Green-- Reverse Output
Red/White--parking brake output
Purple/White--vehicle speed
Blue/White--amp turn on

On my JVC unit I have a green lead labled "Prk sw" and a purple/white labled "reverse".

I also have the remote turn on from the jvc wiring harness.

Prior cars were so much easier. For the remote turn on from the jvc harness do I only send that wire back to the aftermarket amp for subs or do I also need to to tie that in with the rp4 blue/white amp turn on?

Would it suffice to just ground the green Prk Sw lead from the unit as I have done with prior units or do I need to tie that into the rp4 red/white lead?

Does the rp4 green (rev output) need tied in with the jvc unit purple/white (reverse)?


I have no back up camera and no Nav so I dont think the reverse, parking brake output, and vehicle speed are necessary but want to make sure.

Also just wanting to make sure I dont need a 3 way connection for all of the amp turn on leads.

Thanks in advance!

 

[DAlastDON]

Connect the remote out of the head unit to the remote on the GM11. One or two additional amps can be connected to the remote out as well.

The head units harness must be generic for different models. If your head unit does not support those features then just tape up the wires.

 

[IndianaEXT]

Alright so I connected everything I had except for the orange solid wire coming off the RP4 as it had no pair so it was left alone with the other nonessential wires.

Fired up the car and it came on, played radio,CD, and DVD as it should but I hear static as soon as the volume goes from 0 to 1. Its not noticeable once the volume starts to go up but it is very noticeable at low volumes even when there is no audio selected.

Any ideas?

 

[Mooseman]

I had noise like that in mine. I had to add a ground loop isolator between the HU and RP4. I used this one:
https://www.amazon.ca/gp/product/B0049MYXEY/?tag=gmtnation-20

 

[IndianaEXT]

I dont even have any RCAs hooked up at the moment. A sub will be added in near future but right now I get thos static with just the head unit itself powered on....unless I'm missing something?

 

[Mooseman]

Could be electrical noise coming in to the unplugged RCA's.

 

[IndianaEXT]

Update....

Buddy of mine suggested possibly tapping into the ground and then taking that to an extra ground. Still had the static noise after that as well.

Just scratching my head on this one....