Stereo Install Questions

[f5fstop]

Originally Posted by BuzzH3

Thank you for the response. That is very interesting.

From my understanding (and this is just from reading info on the AVIC-Z1), the Z1 uses the speed sensor and an internal gyroscope to determine your current location if you lose the GPS signal. Once the signal is reacquired, it syncs to where the satellites are saying you are. It continuously records this information and the unit becomes more and more accurate the more you drive. So if you are driving in a heavily wooded area or in the city with tall buildings it can still maintain a high level of accuracy.

One more quick question. Where in the engine compartment is the PCM located?

Ok, that makes sense for the need of a speed sensor. However, not sure how often it would be used on the main highways of the US. I travel with a Garmin iQue 3600 for the roads, and I have only lost signals in very narrow canyons for a few minutes, or in long tunnels.

PCM is at the left rear of the eingine compartment, by the coolant bottle.

[kodiakz]

Must use a vss for the nav to function properly and for voice guidance to work at all.

[HummerNewbie]

Originally Posted by kodiakz

Must use a vss for the nav to function properly and for voice guidance to work at all.

Does this just apply to the Z1? D1 doesn't have voice commands so that isn't an issue for me and may nav seems to work just fine. Have talked to others that never hooked up the vss and their systems work just fine as well.

[dеiтайожни]

The N2 also uses the VSS to increase accuracy...if you lose signal it will still have a good idea where you are, incase you can get lost in a tunnel I suppose. I never hooked my VSS in the h3, had it hooked up in my last vehicle though. I can't tell a difference. Nav functions properly, and I still get voice guidance. So must be only on the Z1...which sucks.

[kodiakz]

The Z1 and N3 (can't remember on the D2) have voice guidance that will not work if the vss is not connected. Also, your system will be much more 'spot on' when locating using vss instead of just the gps. We have installed many of the new eclipse models that don't require vss and have noticed that they are not quite as accurate as when the vss is used.

[HummerNewbie]

When I read voice guidance, I was thinking voice commands as in you say the address you want. The Z1 has that feature doesn't it? The D1 does have voice guidance and it works fine without the vss hooked up. I know it will increase the accuracy no matter where you are at but I have yet to have an issue without it. I wonder if your location effects the need for vss or not. I can see being in the mountains making it more important. It certainly won't be like being in the rockies but guess I will find out when we head up to Tellico. Every morning it is off by a couple of blocks but is back on track in a couple of minutes. Not going to get lost within a couple of blocks from my house so not too worried about that

[BuzzH3]

Does anyone know how to remove the antenna from the factory XM box? Does it pull straight out or unscrew?

Thanks

[kodiakz]

Squeeze and pull. Small tab on the cyan plug. You had also asked if you could get 12v and ground at the xm harness which you can. However, it is typically best to get all your grounds at the same point to alleviate any possible ground loop (results in unwanted noise). You may try to get power and ground there and just see if you have any whine or hiss in the system.