Starting problem

[thirdgoat]

Had a problem last week with the Tahoe... dead battery overnight. Nothing was left on, the battery (relatively new) read 1.2 volts. Got it jumped, took it to a shop, and of course, it was fine. They checked the alternator and starting systems, checked out fine. Yesterday morning, I think (because I had to get to work I was in a hurry) it appeared after the alarm was turned off and getting in the truck, I thought the LED lamps in the HVAC control unit were on and the fan running. without the key in the ignition, but again, was rushed, it started, and I was on my way. This morning, went out to start, and all I got was the solenoid engaging (clicking). I asked a neighbor to engage the starter, smacked it with a hammer to no effect. I then observed when the key was to the start position, sparks came from the solenoid/starter area.

Three questions...

 

1. Does this indicate the starter is trashed? (I assume so)

2. Can an aftermarket Alarm (Viper top of the line) draw or could draw enough current

to drain a battery?

3. Does the Body Control Module come into play with the HVAC controls at all? Could

this contribute to my electrical woes?

 

This is a 99 Tahoe 2-door, with 99k miles, and it appears to be the original starter.

 

Appreciate any comments/thoughts

 

Thanks, guys!!!

[peppersac]

They say that your alarm can run off of one of those little 9 volt batteries overnight and not drain it down. My wifes car was doing the same thing but it was the remote wire on her speakers amp. Is there a cannon plug that you can dissconnect from the starter? if so disconnect it over night and if it starts in the moring then it should be your starter.