I'm at a loss... I can usually fix most things on my vehicles, but
this one's got me stuck.

Okay, about a month ago, the LED's (odometer/Radio) in my 02 Tahoe
started flickering, and on occasion the idle would dip below normal,
almost to a stall. Most of the time, I could turn the truck off and
start it again, then it would be normal.

Then, on Wednesday, I went out to the truck, tried to start it, and
absolutely nothing. No dome lights, nothing.

The battery is fine, the alternator is fine. I can't even hook a code
box up to it and get an error code because there is apparently no
current moving.

Does this sound like anything to anyone? Some sort of sensor, or
wiring harness issue? I've tightened any harness that I could reach,
including battery cables. Relay?

Chokeu2 <chokesbox@gmail.com> wrote:

>I'm at a loss... I can usually fix most things on my vehicles, but
>this one's got me stuck.
>
>Okay, about a month ago, the LED's (odometer/Radio) in my 02 Tahoe
>started flickering, and on occasion the idle would dip below normal,
>almost to a stall. Most of the time, I could turn the truck off and
>start it again, then it would be normal.
>
>Then, on Wednesday, I went out to the truck, tried to start it, and
>absolutely nothing. No dome lights, nothing.
>
>The battery is fine, the alternator is fine. I can't even hook a code
>box up to it and get an error code because there is apparently no
>current moving.
>
>Does this sound like anything to anyone? Some sort of sensor, or
>wiring harness issue? I've tightened any harness that I could reach,
>including battery cables. Relay?

Battery ground cable - where it connects to the block, or frame, not
at battery end. I've seen these corrode inside, under the insulation
at the battery end, also. As a diagnostic, you might connect a jumper
cable from the negative battery post to the engine block. Do not
crank. But now see if dome light, headlights, and so on work. Then
disconnect jumper cable. If they go back out, you know the problem is
the battery grounding cables.

If (with the jumper cable) nothing still works, the problem is
elsewhere (including possibly the POSITIVE cable.

I've also seen what you describe when the ignition switch fails. Some
circuits do not get energized.

See what others have to say. My experiences (with the switch) are on
vehicles 5-8 years older than your Tahoe.

"Chokeu2" <chokesbox@gmail.com> wrote in message news:0a90c1b1-e2b3-4186-aed3-46adbed238ef@l39g2000yqn.googlegroups.com...
> I'm at a loss... I can usually fix most things on my vehicles, but
> this one's got me stuck.
>
> Okay, about a month ago, the LED's (odometer/Radio) in my 02 Tahoe
> started flickering, and on occasion the idle would dip below normal,
> almost to a stall. Most of the time, I could turn the truck off and
> start it again, then it would be normal.
>
> Then, on Wednesday, I went out to the truck, tried to start it, and
> absolutely nothing. No dome lights, nothing.
>
> The battery is fine, the alternator is fine. I can't even hook a code
> box up to it and get an error code because there is apparently no
> current moving.
>
> Does this sound like anything to anyone? Some sort of sensor, or
> wiring harness issue? I've tightened any harness that I could reach,
> including battery cables. Relay?

90% sure you have a bad ground somewhere. Start at the battery (contacts),
cables, all the starter bolts in front (not the starter mount bolts, the electric ones) then the
motor ground strap (in the back of the motor, pass side).

Check the firewall relays behind the black cover on the pass. side (inside the motor
area). Make sure all the bolts are tight, and the contacts are clean.

Then of course, make sure the battery has a charge, and that the alt is charging (if you get it started).


As you prob. know, it's a pain chasing electric problems, but most of the time, no power = bad ground.

HDS

Thanks guys... Awesome guidance.

Interestingly enough, I had a meeting this morning, so I figured I'd
just try to start the Tahoe and see what happens... The doggone thing
fired right up! Charging fine, running fine, no flickering, no signs
of anything... So I opted to push my luck by driving it to my meeting,
knowing I'd be steamed if it failed to start when I was done. Not a
problem, she fired right up with no trace of the problem.

Now thats not to say that it will not start flaking again, because it
will; it is just a matter of time.

I'm going to give your guidance a shot, failing that, I'm going to
have to suck it up and take her in.

Thanks a ton!
Regards,
Brian

"Chokeu2" <chokesbox@gmail.com> wrote in message news:f28ad6da-0fbe-4e05-88a6-bdd3cafab84f@w3g2000yqc.googlegroups.com...
> Thanks guys... Awesome guidance.
>
> Interestingly enough, I had a meeting this morning, so I figured I'd
> just try to start the Tahoe and see what happens... The doggone thing
> fired right up! Charging fine, running fine, no flickering, no signs
> of anything... So I opted to push my luck by driving it to my meeting,
> knowing I'd be steamed if it failed to start when I was done. Not a
> problem, she fired right up with no trace of the problem.
>
> Now thats not to say that it will not start flaking again, because it
> will; it is just a matter of time.
>
> I'm going to give your guidance a shot, failing that, I'm going to
> have to suck it up and take her in.
>
> Thanks a ton!
> Regards,
> Brian
-------

Don't temp fate! LOL. Yes.. the problem is still there. More then ever, I think you have a
bad ground cable (itself), or it's connections. Even if the cables look great, they will corrode
inside (turn all green). Sand or wire brush the terminals at the battery.

HDS