need help on finding the best place/way of getting Accessory power.....info on wire color codes will be perfect..

Thanks

need help on finding the best place/way of getting Accessory power.....info on wire color codes will be perfect..

Thanks

What are you connecting, and where are you locating the device?
There is accessory power in the A-pillar, and plenty of spots under the I/P and hood.

18 gauge white or brown on the back (inside) of the drivers fuse panel.

There is a fuse panel inside?
I have noticed that the yellow wires in several locations are Acc power. I would double check with a meter just to be sure.

I actually need to connect 3 wires to power up headrest monitors..BATTERY..ACC..GROUND..now as far as the battery wire..do I really need to get it from the battery or is there a wire on the inside already that I can tap ?

Thanks

Fuse panel directly inside the driver's door on the side of the dash, and I have never personally seen a yellow wire in a gm vehicle that is anything other than starter or other. Use a meter/light to test.

Do not need to go to the battery for headrest monitors. There are a couple orange wires in the driver's side fuse panel that are accessory 12v constant and are fine. There is also a heavy guage wire under the seat for the power seat motor that can be tapped. You can also get ground under the seat, but will need to go either to the amp (right inside the back panel of the center console) or to the under-dash for a switched wire. You really only need to go to the battery for heavy current draw devices.

kodiakz
You have not worked on many GM cars...yellow is the color GM has used for acc power for many years, and on the H3 is used for retained accessory power circuit (power that stays on after the ignition switch is turned off, and before a door is closed). Therefore, any component that is on the RAP relay is powered by a yellow wire.

However, that is minor, when compared with the information you give for the location of the amplifier. That box under the rear of the console on an H3 IS NOT an amplifier. IT IS THE AIR BAG MODULE, called the SDM (sensing and diagnostic module).
WHATEVER you do, DO NOT connect into the SDM. Messing with this device may deploy all the air bags in the vehicle. This is not only dangerous, if your head is near a bag when it is deployed, it is also very costly to replace the bags and parts of the I/P. Needless to say, this is not covered under warranty but can nominate someone for the Darwin award.

The saying for anyone who is familiar with GM vehicle wiring, is never mess with a wire that comes off a YELLOW connector. GM uses yellow connectors for the air bag system wiring.

In addition, there is NO fuse box under the left I/P, the only fuse panel is under the hood.

As for the amp, on the H3 it is located at the sub-woofer, rear left cargo area. Onstar module under center of I/P, XM receiver above glove box.

I will say you are correct when telling the person to connect to one of the orange wires under the seats for B+ power. But they do have to have power seats.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Game Over:
need help on finding the best place/way of getting Accessory power.....info on wire color codes will be perfect..

Thanks </div></BLOCKQUOTE>

As someone already stated, B+ is obtainable from under the seats. For accessory power, there is a harness that runs down the driver's side of the vehicle; look for a yellow wire, that is the RAP circuit and is hot in ACC or Run. This will be the circuit that goes to the rear wiper/washer.
If you do not have power seats, I BELIEVE, on the right side of the vehicle, is the harness that runs to the rear ACC plug and that is hot at all time (B+).
Just pull up the sill moldings on the doors and look under the carpeting. If the ACC plug harness does not run down the passenger's side, then it has to run down the driver's side.

f5stop, I believe that the reference for the amp and fuse panel was for an H2 not an H3, but if I misread then my bad. I have actually been working on GM vehicles for 17yrs and if they are using a yellow wire for acc or rap that is news to me. I have seen pink, white, blue, brown, but never yellow. I typically do not tap into wires that are designated for single use accessories (like the rear wiper) as 1. the dealer will instantly blame your install for any problems 2. they can easily induce unwanted noise 3. many of these components are on databus lines now. I find that it is just a good idea to tap into wires that are designated to run many accessories or that are heavey current, dumb device (like the 12v constant under the seat). I will admit that my knowledge of the H3 is far less than that of the H2 or other GM vehicles of which I know more about than most of the dealers I do work for.

edit: just reread my post and I did say that the amp was unser the console--my bad!! It was late, long day, and I had just finished doing nav/rewire in an H2 so that was fresh in my mind. Now that I think back a few years, GM did use yellow for acc on some circuits like radio turn on, but it has been a few years!! Feel free to slap me again next time I drift into the wrong lane

Not going to slap you or anyone. I sort of figure you might be talking H2 when mentioning the fuse panel. I just wanted to make sure no one taps into the SDM, now that is a component that can do a lot of damage.
Yellow has been common for ACC on GM's for many years, and now instead of coming off the ignition switch to many accessories, it comes from the RAP relay, turned on by the BCM. Look at all the GM schematics on the eSI system. (In fact my corvettes have a three wire bundle just above the BCM; one black, one yellow, one orange for connecting accessories. We normally like to say those were designed in for a radar detector.)


As for tapping into databus components, normally not a problem if low current draw, and you are only tapping in for power. As long as you don't try and tap into a bus line, or the ground side, everything should be ok.
If installing a large current line, just connect to a yellow for a switch side of a relay, and run the power circuit directly off the battery B+ side.
To tap into something like the wiper motor, just tap in far down the line. If done correctly, you will not be cutting power to the component, and if it fails, a tech will check at the component for power, find it and move on to other diagnosis.

here's what I did off the GM24 harness:

- orange wire for 12v constant
- gray for ACC

finally done wiring the headrest monitors...still need some positioning adjustment and still thinking about flush mounting on the headrest, just a lil' tricky not having a headrest shell/shroud for the monitors that I am using. I know...posts are useless without pix still charging the camera's battery

Make sure to cut WAY small first on the headrstt!!
f5stop--thanks for belaying the smack down (still wouldn't wnat to try the tying into multiplex wires though-even with low curreent draw)

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Game Over:
here's what I did off the GM24 harness:

- orange wire for 12v constant
- gray for ACC

finally done wiring the headrest monitors...still need some positioning adjustment and still thinking about flush mounting on the headrest, just a lil' tricky not having a headrest shell/shroud for the monitors that I am using. I know...posts are useless without pix still charging the camera's battery </div></BLOCKQUOTE>

Curious about the gray wire. If you turn on the key, but do not start the engine, does it power up then go dead, until the engine is started?

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by kodiakz:
Make sure to cut WAY small first on the headrstt!!
f5stop--thanks for belaying the smack down (still wouldn't wnat to try the tying into multiplex wires though-even with low curreent draw) </div></BLOCKQUOTE>

As long as you don't tap into an actual bus or signal wire to a component/sensor, you should be alright.
On my '03 vette, I installed resistors into the BCM power wires to the Radio/HVAC (corvette has some weird wiring) in order to change out all the backlights in these components with blue LEDs. Never set a code, never caused a problem; other than I had the Vette torn apart for three weeks. Then I changed all the switches and compartment lights to LEDs (switches-blue, compartment lights-white).

That sounds like a project!! How did you determine the correct resistor values to use?

Since it was a Vette, it took twice as long.
My (our) mistake was checking the voltage drop on the radio, and assuming it was the same on the HVAC head. The radio was fed battery voltage but was dropped to 9.6V on the circuit board. We calculated the voltage drop for the radio, and installed the correct resistors inline with each LED. We also had to shave the head of the LEDs with a dremmel. (Due to the shape of the LED, they direct their light in a pinpoint method, shaving the head flat allows the LED to spread out the light similar to an incandescent bulb.)
Did the same for the HVAC head; installed all back, turned on the lights and you could see the HVAC unit in broad daylight.
Found the HVAC unit is fed full battery voltage from the BCM. Removed the HVAC head, and figured a new voltage drop requirement, installed larger resistors.
Switches were quite easy, just install a resistor inline with the LED insert in the bulb plug, and install.
As I say, it was fun, but I would NEVER do it again....never I say.

So did you end up with the electroluminescent look?

"Onstar module under center of I/P"

Doug where exactly is the Onstar module?
Center of I/P? (inside panel??) where?
Just want to know where they are going in my truck when the module is replaced....

I had my H3 in on sat for the 6-disc programming and to really have the Onstar diagnosed I have b=never been able to get to thm via the mirror mount buttons.

The told me on saturday the module must be bad 2 weels to get and it neds to be installed and set up while on the phone with Onstar tech..

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by kodiakz:
So did you end up with the electroluminescent look? </div></BLOCKQUOTE>

Actually, I ended up with a damn headache , but is sure did look cool at night.