Where is the g200 ground located on a 2002 silverad 2500hd 6.0. HOw do i get to it. i read its on the A pillar

There are too many to count.
Starting in about 1985, when cars & trucks began to have plastic and fibreglas parts, separate ground wires ran from every electrical part to the "universal" ground wires, that ran all over the vehicle.
Have a knowledgeable mechanic show you these.
God bless your efforts.

seems to be a ground circuit . Do you know how to do automotive electrical testing ? specifically voltage drop testing ! There are no grounds in the steering column . The power door locks ground at G - 200 an G-203 G200
In the HVAC harness, on the right side of the I/P near the A-pillar below the I/P top cover
Power and Grounding Component Views
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G203
In the I/P harness, on the left side of the I/P near the A-pillar below the I/P top cover

Is the air bag light lit ? Clock spring ! do you know what that is . No horn . The battery drain needs to be diagnosed doing parasitic drain testing .


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25842326 How do I gain access to G200 ground point?

seetvshownow.science/.../t25842326-remove_dash_or_gain_access_g20...
... G200 ground point? - Pontiac 2002 Montana question. ... 2002 Pontiac MontanaDetail Question How do I gain access to G200 ground point? Solution: source ...

you need to first check the antenna amplifier which should be located in the left rear pillar behind the interior cover panel, also check the ground connection there.

Check for that fuse in a fuse panel under the dash.
That second wire from the old light is a ground wire, whereas the new light's socket is case grounded if there is no ground wire for the light. If the fuse for the tail lights is good, check if the tail lights lost a ground .

Before assuming - look at a wiring diagram an check power an grounds to the HVAC control module . There are no relay's involved ,two fuse's .DRL/TEMP/HTD ST fuse 10amp - location I/P - instrument panel fuse box & Radio fuse 10amp -location underhood fuse box. Ground point - G200 .Do you know how to test automotive electrical circuits using a wiring diagram an a DVOM - digital volt ohmmeter ? Free wiring diagrams here http://www.bbbind.com/free-tsb Enter vehicle info. year , make , model an engine size. Under system click on HVAC ,then under subsystem HVAC controls will pop up automatically . Click the search button , then the first blue link .
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If power an ground are good ? replace the HVAC module .

You dont say what Model Llimited) engine ( 6? 8? )or Manual or Auto temp control. but maybe check the ground wire for the blower. G200 black wire, which ends up under console. check the black wire at the motor, if it has voltage on it, the ground is bad. the power wire should have 12V

Sounds like a gound problem to me. Check you headlamp grounds. The ground circuits for your headlamps actually go through the underhood fuse block, then to the headlamp switch, then through Splice Pack #SP203 (Located under the left side of the dash it is bolted to the left "A" pillar) , then to ground #G200. (Which is actually the bolt that is holding the splice pack.) I have seen corrosion in the splice packs several times. You may want to disassemble it and clean the terminals. A LIGHT coat of dielectric grease usually works pretty good to prevent it from doing it again.

the brake light fuse should be in the fuse box under the hood,but you might find a small fuse box under the dash as well.....hope this helps.....cheers

Hi:
to figure out what is going on with your truck, you need to have someone with an OBD2 scanner read your codes to see what is tripping the light. A gas cap is a usual suspect, but there are hundreds of other things too. Auto parts stores, like Autozone, will usually read your code for free, and tell you what is going on.