VSS in radio harness?

[deicustoms1]

According to another thread, the VSS can be found in the smaller radio connector. Mark M said he only had 2 wires from that connector, and he had the base radio. I also have the base radio, but mine has like 5 wires in there.

So, another person says the drk.gr/white wire is the vss in that topic. And then cautions that there are 2 drk.grn/white wires. I only have 1 green/white wire in that connector. I've tapped the green/white wire, and the pink/black wire, I'm not getting a speed pulse. What is going on?!

[deicustoms1]

According to another thread, the VSS can be found in the smaller radio connector. Mark M said he only had 2 wires from that connector, and he had the base radio. I also have the base radio, but mine has like 5 wires in there.

So, another person says the drk.gr/white wire is the vss in that topic. And then cautions that there are 2 drk.grn/white wires. I only have 1 green/white wire in that connector. I've tapped the green/white wire, and the pink/black wire, I'm not getting a speed pulse. What is going on?!

[f5fstop]

VSS wire is in cavity E and it is a dark green/white wire and by the updated wiring schematics it is only avaiable with the navigation system. If you have XM the XM Right audio signal comes in on terminal H and it is dark green/white.
The wire might be there standard for any application, but only used by the NAV, or GM made a wiring change.

[deicustoms1]

Yeah, I have XM.

But the only colors in there are

green, orange, black, brown, pink, purple (with stripes)

I looked for some marking on the connector, and I don't see anything. Could you tell me where cavity E is? I believe purple is at one end, and pink is at the other end. Like is it the 2nd , 3rd, 4th one from the end? thanks

[deicustoms1]

I see a little G in one corner. In that corner the wires are:

purple, green, brown, black, orange, pink

pink is in the corner slot, that shows an M

but pink should be L if its alphabetical....

the plug we are talking about is the smaller of the 2 plugs that plug into the stock radio right?

[deicustoms1]

I have auto volume setting on the stock radio, doesn't that require the speed pulse?

[f5fstop]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by deicustoms:
Yeah, I have XM.

But the only colors in there are

green, orange, black, brown, pink, purple (with stripes)

I looked for some marking on the connector, and I don't see anything. Could you tell me where cavity E is? I believe purple is at one end, and pink is at the other end. Like is it the 2nd , 3rd, 4th one from the end? thanks </div></BLOCKQUOTE>

Green - If this is green with white strip, and in cavity H, it is the Right Audio signal from the XM receiver.
Orange (with black stripe) - Cavity L Remote playback device

Black (with white stripe) - Cavity K XM audio common
Brown (with white stripe) - Cavity J XM left audio signal
Pink (with black stripe) - Cavity M Remote playback device
Purple (no stripe) - Cavity G Class 2 serial data

Looking at the connector end, A is bottom left corner, M is upper left cornet, G is upper right, F is lower right (I is not used, to remove any similarity to 1).

The speed sensity volume is most likly controlled by the BCM as it is on other vehicles, via the class 2 circuit.

[deicustoms1]

Ok, that makes more sense. So I can't tap into any wire in the radio harness to get vss then? I have to go into the engine compartment?

[MarK M]

or passenger kick panel... but i've tapped into several wires; wires mentioned in the searches and couldnt get the VSS to work nor the slope.

soooo confused!

[kodiakz]

Mark, when you put the radio into diagnostic mode, what does it say in the vss column? Should say studying with the correct mph read out.

[f5fstop]

You can always get a VSS speed from the PCM or BCM. I believe the PCM signals the BCM with the speed, which the BCM translates and forward to the I/P cluster via the class 2 wire.
I could swear the earlier GM schematics had the VSS circuit coming into the radio; now it is clearly stated in the schematics that the wire is only with the NAV system, which uses the same connectors.
I know on my Vette, the BCM controlled the speed sensitive volume, so I have to assume on these new radios, the BCM is also controlling the volume, and without a VSS wire into the radio, it pretty much confirms this assumption.
If I have time this weekend, I'll look over the schematics for the PCM to BCM. Or, there has to be someone here who has attached to the VSS at another location.

[deicustoms1]

That would be great if you could find the vss wire from the pcm to the bcm. Thanks for looking.

[MarK M]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by kodiakz:
Mark, when you put the radio into diagnostic mode, what does it say in the vss column? Should say studying with the correct mph read out. </div></BLOCKQUOTE>

i'll check that out this weekend. The wifes been driving the H3. I swear when I bought it she was like why a hummer... now who keeps driving it!

one note... I do get a correct MPH reading which puzzles me.

[deicustoms1]

The MPH comes from the hybrid sensor in the unit, and also GPS to calculate speed. Next time you are working on it, set it to vehicle dynamics and tilt the headunit, it will give you a mph reading.

[f5fstop]

The GM wiring diagrams show no speed signal going to the BCM. So, if there is no speed signal to the BCM I have to assume one of two things.
1. Wiring schematics are incorrect.
2. Speed signal from the PCM to the BCM is sent via the class 2 serial data wire.

However, there is a speed signal wire that comes off the PCM, and it might be the wire that goes to the NAV system is equipped with the NAV unit.
It comes off pin 21 of the blue connector. Whether or not that wire is there depends. It might not be except on vehicles with the NAV unit.

I have to say again, I could swear in the older Hummers, there was a speed signal at the radio connector; regardless if it had NAV or not. I could be mistaken, but some people are getting this speed signal from someplace.

I can check on Monday, with the validation engineer and see if he has validated the H3 schematics, and see if he remembers anything in regard to the PCM to BCM wiring being fudged up.

[deicustoms1]

You are right, there is a vss wire at the radio connector (on some models). I've checked out several places and people have been getting it there.

According to DirectWire, speed sense is dk. green/white pcm, blue plug, pin 21. note: Also found in the radio harness on some models. I must have the model that doesn't have it there...

I've been hesitant to do that wire though, but I'm guessing it is there. I'd really perfer to get it inside the vehicle, I hate messing with those plugs, I played with them a little and there wasn't really room to work with it.

If you have a chance to find out where I can pick it up inside the car that would be great, otherwise next time I gotta get into the pcm plugs I'll just do it then. Nav works ok, so no big rush now. thanks

[f5fstop]

This is bugging the sh** out of me. Today, after installing my signal mirrors, I'm going to pull the radio and see what the wires are back there on that connector.
GM could have removed all unnecessary wires from the connectors for a cost savings.

[deicustoms1]

Just wondering...I tapped into the purple wire, which I now see is a data cable. Is that bad? I didn't get a cel or anything, but could that have messed anything up?

[kodiakz]

Untap that wire from the data line--that could cause you serious problems and will not (without some sort of interface) give you a vss signal.

[deicustoms1]

Yeah, I only had it tapped for a few minutes because I was pretty sure that was the vss wire at the time.