Im having a problem with a deisel gmc topkick getting air in the glass bulb

you may be able to find a diagram of the air brakes on your 2000 GMC C7500 Kodiak Topkick by doing the following:

1. Check the owner's manual: Your owner's manual should include a diagram of the air brake system for your specific vehicle.
2. Search online: There are many online resources that may have a diagram of the air brake system for your vehicle. You can try searching for the make, model, and year of your vehicle along with the term "air brake diagram" to see if you can find a diagram that way.

Try this website. The fuse panel is in the dash near the steering wheel, probably at about knee height. Some versions have the cover held in place with small bolts. (possibly 8mm or 10mm).

https://www.autogenius.info/gmc-c-series-mk2-second-generation-1990-1999-fuse-box-diagram/

Check for bad wiring (broken ground wire) and for blown light bulbs that can short the power supply.

Before going there, check your INERTIA SWITCH (INTERTIAL CUTOFF SWITCH). A small accident or a sharp bump can cause the cutoff switch to trip. The switch is located adjacent to the passenger side rear shock tower, and there is a pushbutton to reset (on most Topkick tucks). Carbureted Topkick trucks do not have cutoff switches, and some custom trucks have the inertia switch relocated.

could be 2 separate issues; burned out bulbs and a faulty alarm. Test bulb socket to see if it has power separate from the alarm.

Someone please call me 3365179318 I have a 1992 gmc topkick 366 engine and I noticed when I turn the key the fuel pump is not coming on. So I’m trying to find the fuse or relay for it to see if it’s maybe bad because the fuel pump ain’t even a year old. Someone please help me lol

Great question with no answer.

they have a extnded warranty on the speedometer cluster 7 years or 70,000 miles

I would suggest just using a redundant wire to use for your tach.

I hope this helps.
Roy

Mass air flow sensor.