Truck won't run without stereo?

[smburnette]

I tried searching, but found nothing. If this question has been covered, I apologize.

I purchased a new toy last week to play with.. Its a 1991 Silverado, 2wd, 350, 5 speed.. The previous owner had removed the tape deck, and slid a new head unit in its place.. He simply ran new power and speaker lines.. I ordered the dash panel, wiring harness, antenna adapter, and filler box to do the install correctly.. Yesterday, I decided to do some prep work and remove all the existing components.. I had removed both the controls in the dash, and the main unit under the dash.. I tried to start the truck, and it had no fire, and no fuel.. After checking everything I could, I plugged the stereo back in.. It fired the first crank.. Remove radio, nothing, install radio, it runs..

Is this normal??

And if it is, will the correct wiring harness adapter allow me to remove that box, or will it always have to be present?

 

[great white]

Dunno what you've got going on there.

I had both the remote head piece and the amp (actually, it's the radio) under the dash removed from my 89.

No issues.

 

[Ruger_556]

That's odd... I've got everything factory removed (Box in the dash, tape deck, and control head) and running a Kenwood stereo. Never had that problem but I didn't try to start it without the adapter plugged in either

 

[lha1992]

Thats really weird it won't run without the old stereo plugged back in.

First off check your grounds possibly! Maybe its shorting out somewhere an the radio is whats making it start? Idk its a try to look at so

Sent from my GT-I9100 using Tapatalk

 

[Ruger_556]

Bad wire somewhere and the computer is finding power through the radio circuit while it's cranking?

 

[lha1992]

Bad wire somewhere and the computer is finding power through the radio circuit while it's cranking?

Exactly! Essentially shorting through the stereo because of the bad wire somewhere an getting power from the radio circuit.

Maybe check the fuses also an check your grounds at the computer behind the glove box.


Sent from my GT-I9100 using Tapatalk

 

[Ruger_556]

Exactly! Essentially shorting through the stereo because of the bad wire somewhere an getting power from the radio circuit.

Maybe check the fuses also an check your grounds at the computer behind the glove box.


Sent from my GT-I9100 using Tapatalk

I've had something similar happen on a truck where the positive battery cables had a 1.8v drop and the pulled what it needed through the power distribution block in the cab. The problem was that the computer is switched on with the power block (Key on power) so it killed switched power to the computer while cranking. Twin 00 positive cables and it stole the computer/key on power circuit to crank This wasn't on a GMT400 but the theory applies.

 

[low4x4]

maybe the radio is part of a anti-theft device...I knew a guy that had a car, you had to step on the brake to start the car

 

[thz71]

Im gona have to say its wired into an anti theft device